front; eyes near the front, but not marginal. Length 13""; breadth scarcely "". Vermiculus lineatus, Dalyell, Pow. Creat. ii. 90. pl. 10. f. 19, 20. Hab. Coast of Scotland, Dalyell. 2. C.? flustræ, filiform, acute at both ends, pellucid, dark-grey or brownish, with a darker line in front; eyes black, placed on a pellucid portion in front. Length "". Ascaris flustræ, Dalyell, Pow. Creat. ii. 92. pl. 10. f. 27. Hab. Coast of Scotland amongst Flustræ, Dalyell. 14. TETRASTEMMA, Ehrenberg, 1831. Tetrastemma, Oersted, Entw. Plattw. 84. Dies. Syst. Helm. i. 256. Char. Acephalous, the body linear-elongate, flattish, with four eyes placed in a quadrangle in front: mouth terminal. 1. T. varicolor, body rounded in front, tapered at the tail; eyes in a square; the front unspotted. Length 10-15""; breadth 1"". Var. a. cream-yellow. Planaria quadrioculata, Johnston in Zool. Journ. iv. 56. Nemertes quadrioculata, Johnston in Mag. Zool. & Bot. i. 535. pl. 17. Prostoma quadrioculata, Johnston in Ann. & Mag. Nat. Hist. xvi. 436. Hab. The shore between tide-marks. 2. T. variegatum, cylindrical, rather obtuse at both ends, variegated red and white, with a white line down the back. breadth 1". Length 8""; Vermiculus variegatus, Dalyell, Pow. Creat. ii. 91. pl. 10. f. 25, 26. Hab. Shores of Scotland, rare, Dalyell. 3. T. algæ, linear-elongate, widest in front, siskin-green tending to yellow or to brown. Length 4""; breadth "". Planaria algæ, Dalyell, Pow. Creat. ii. 117. pl. 16. f. 24, 25. Hab. Among marine algæ, Dalyell. Obs. The motion is very swift. 15. BORLASIA*. Borlasia, Johnston in Mag. Zool. & Bot. i. 536. Char. Body linear-elongate, contractile, somewhat compressed, soft, even and continuous: head indistinctly defined, sometimes with a fissure on the sides: eyes four to sixteen, separate and submarginal: mouth terminal, the oesophagus unarmed with horny stylettes. 1. B. olivacea, linear-elongate, tapered posteriorly, of a dark olive colour with a red spot in front; eyes from four to eight. Length 3-6"; breadth 1"". Planaria bioculata, Johnston in Zool. Journ. iv. 56. Nemertes (Borlasia) olivacea, Johnston in Mag. Zool. & Bot. i. 536. Hab. Between tide-marks. 2. B. octoculata, of a uniform light reddish-brown colour; eyes six to eight, placed in opposite pairs on the sides of the head. Length 3"; breadth 14"". Planaria octoculata, Johnston in Zool. Journ. iv. 56. Nemertes (Borlasia) octoculata, Johnston in Mag. Zool. & Bot. i. 537. Borlasia octoculata, Johnston in Ann. & Mag. Nat. Hist. xvi. 434. Nemertes octoculata, Oersted, Entw. Plattw. 91. Dies. Syst. Helm. Hab. Under stones, between tide-marks. 3. B. purpurea, narrowed at both ends, of a uniform purplish-red colour, paler underneath; eyes six to eight, marginal. Length 2-3"; breadth 1"". Nemertes (Borlasia) purpurea, Johnston in Mag. Zool. & Bot. i. 537. pl. 18. f. 3. W. Thompson in Ann. & Mag. Nat. Hist. xviii. 388. Nemertes purpurea, Oersted, Entw. Plattw. 91. Dies. Syst. Helm. i. 275. Borlasia purpurea, Johnston in Ann. & Mag. Nat. Hist. xvi. 434. Hab. Between tide-marks, at the roots of algae and corallines. (a) Berwick Bay, Dr. Johnston. 4. B. gesserensis, linear, obtuse at the ends, greenish, sometimes *This name was substituted for the Lineus of Simmons by Oken in 1815. It has been since used, in other applications, as a generic appellation, and ought, perhaps, to be discarded. tending to brown or pale carnation; eyes six or more around the anterior margin. Length 31"; breadth 1"". Planaria gesserensis, "elongata, viridis, pone caput rufa," Müll. Zool. Notospermus gesserensis, Dies. Syst. Helm. i. 260. Gordius gesserensis, Dalyell, Pow. Creat. ii. 73. pl. 10. f. 5. Hab. "Under stones on the shore," Dalyell. Obs. "A slit below indicates the mouth. Colour universally different shades of green; sometimes tending to brown or pale carnation. Numerous lighter narrow circles, at considerable intervals, with a minute pale speck on the side of each, environ the body, resembling faint annulations." Dalyell.-Oersted conjectures that this species may be the same as our Borlasia olivacea (Entw. Plattw. 89). 5. B. striata, black, with many parallel whitish or cream-coloured lines extending from one extremity to the other. Length 1-4'; breadth 1"". Borlasia striata, Rathke in Nov. Act. Nat. Curios. xx. 231. Nemertes striata, Oersted, Entw. Plattw. 92. Dies. Syst. Helm. i. 274. Hab. The littoral zone. Obs. The fragment in the collection is about 3 inches long. It closely resembles Lineus longissimus. The eyes are in a line, on a white space, on each side of the head, and are hence very visible. There are seven pale lines on the dorsal surface, one on each side, and three on the ventral surface. (a) Falmouth, W. C. Cocks. 16. OMATOPLEA. Prostoma (-), Dugès in Ann. des Sc. nat. xxi. 74 (1830); and in Nemertes, Johnston in Mag. Zool. & Bot. i. 534 (1837). Char. Body linear-elongate, contractile, somewhat compressed, soft and even head continuous with the body, indistinctly defined, with or without a shallow fissure on each side, marked with two approximate spots on the dorsal aspect, and with several eyes, scattered or clustered: mouth terminal, the œsophagus armed with horny stylettes: anus anterior? 1. 0. gracilis, of a uniform olive colour, very long and linear, or a little narrowed posteriorly; eyes numerous, arranged on the margins of the head. Length 20"; breadth 1"". Nemertes gracilis, Johnston in Mag. Zool. & Bot. i. 534. pl. 17. f. 1. Hab. Under stones near low-water mark. Obs. This is probably the "small and slender animal" described by Sir J. G. Dalyell, Pow. Creat. ii. 65. pl. 8. f. 3–6. 2. O. rosea, linear-elongate, rounded at both ends, of a uniform cream-colour or roseate; eyes many, in four clusters anterior to the reddish cardiac spots, the posterior clusters small. Length 3"; breadth 2". Fasciola rosea, Müll. Verm. i. ii. 58. Planaria rosea, Müll. Zool. Dan. Prod. 221; Zool. Dan. ii. 31. tab. 64. f. 1, 2. W. Thompson in Ann. Nat. Hist. xv. 321. Turt. Gmel. iv. 62. Bosc, Vers, i. 299. Planaria lactiflorea, Johnston in Zool. Journ. iii. 489. Nemertes lactiflorea, Johnston in Mag. Zool. & Bot. i. 535. pl. 17. Polystemma roseum, Oersted, Entw. Plattw. 92. Omatoplea rosea, Dies. Syst. Helm. i. 251. Gordius albicans, Dalyell, Pow. Creat. ii. 73. pl. 10. f. 5 a, 6. Hab. Between tide-marks. (a) Berwick Bay, Dr. Johnston. 3. O. alba, whitish, with fourteen eyes anterior to the cardiac spots, "the first four on each side near the margin of the body disposed in a line, and at equal distances from each other; considerably behind them are three at each side disposed in a triangular manner, the base towards the head of the worm." Length 2"; breadth 1"". Borlasia? alba, W. Thompson's Rep. Brit. Assoc. 1843, 271; Ann. Hab. Under stones between tide-marks. 4. 0. melanocephala, linear-elongate, yellow or yellowish-green with a dark or black head; eyes four, arranged in a quadrangle. Length 11"; breadth "". Nemertes melanocephala, Johnston in Mag. Zool. & Bot. i. 535. pl. 17. Prostoma candidum? Dugès in Ann. des Sc. nat. xxi. 74. pl. 2. f. 3. Hab. Under stones between tide-marks, in wet sand. Obs. The Tetrastemma obscurum of Dr. M. S. Schultze is nearly allied to this species; and Schultze has proved that his species is viviparous (Naturg. Turbell. 62. tab. 6. f. 2-10). (a) Berwick Bay, Dr. Johnston. 5. 0. pulchra, linear-elliptical, rounded at both ends, of a flesh-red colour, with a series of scarlet spots along each side, or of a uniform aurora-red; eyes numerous, clustered in front. Length 1-2"; breadth 2-3"". Nemertes pulchra, Johnston in Mag. Zool. & Bot. i. 536. pl. 17. f. 6. Omatoplea pulchra, Dies. Syst. Helm. i. 252. Vermiculus rubens, Dalyell, Pow. Creat. ii. 89. pl. 10. f. 13–18. Hab. The coralline region. 17. STYLUS. Spinifer, Dalyell, Pow. Creat. ii. 77 (1853). Char. Body linear-elongate, flattish; the head indistinctly defined, continuous with the body, oculate, and with a fissure on each side; the posterior end terminated with a cartilaginous style. 1. S. viridis, uniform mountain-green; the nuchal grooves very distinct; posterior extremity narrowed, with a style one-sixth the length of the body. Length 3"; breadth 14"". Gordius viridis spinifer, Dalyell, Pow. Creat. ii. 78. pl. 11. f. 1. Hab. Coast of Scotland, rare, Dalyell. 2. S. purpureus, of a deep red purple colour; head somewhat spathulate, obtuse, with a fissure on each side; posterior extremity narrowed and terminated with a roughish style. Length 8"; breadth 1"". Gordius purpureus spinifer, Dalyell, Pow. Creat. ii. 78. pl. 11. f. 2-4. Hab. Coast of Scotland, rare. 3. S. fragilis, of a uniform reddish-orange colour; the front pointed. Length 34"; breadth 2""; anal style 6"". Gordius fragilis spinifer, Dalyell, Pow. Creat. ii. 79. pl. 11. f. 5. Hab. Coast of Scotland, Dalyell. 4. S. fasciatus, semicylindrical, almost linear; the head obtuse, multocular; the anal style long and flexible; orange or reddish |