McIntosh, W. C. (1873-1874). A monograph of the British Annelids. Pt. I: The Nemerteans. The Ray Society, 1873: pp. 1-96, pls. I-X; 1874: pp. 97-214, pls. xi.-xxiii
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McIntosh, W. C.
1873-1874
A monograph of the British Annelids. Pt. I: The Nemerteans
The Ray Society
1873: pp. 1-96, pls. I-X; 1874: pp. 97-214, pls. xi.-xxiii
The following review of the genera and species of British Nemerteans described by MCINTOSH (6) will afford at the same time a condensed account of the more important anatomical characters, distinguishing the suborder and its divisions, families, genera, &c. "Nemertinea. Worms with more or less elongated, soft, ciliated bodies, furnished with a thick glandular cutis, beneath which the body wall is composed of several strong, specially disposed muscular layers; nervous system composed of 2 conspicuous ganglia, connected by a double commissure, and 2 main lateral trunks running backwards to the end of the body. Through the centre of the body cavity, and entirely beneath the nerve commissures in front, passes the digestive system, a ciliated canal with 2 well marked divisions, and 2 apertures, an oral anteriorly, and an anal posteriorly. Circulatory system consisting of a series of closed contractile vessels. The complicated proboscis is placed along the median line of the back, surrounded by a special muscular sheath, within which it glides in a highly organized corpuscular fluid, passing in front between the commissures of the ganglia, while the digestive tract is placed inferiorly. Sexes separate in the majority, oviparous or ovo-viviparous; sexual organs in the form of sacs placed between the muscular wall of the body and the digestive canal." A. Enopla. Proboscis furnished with stylets. Blood-vessels more differentiated than in the Anopla. The young, as far as is known, do not undergo any noteworthy metamorphosis during their growth. I. Amphiporidoe. Nerve-ganglia rather rounded, somewhat double; lateral nerve-trunks placed within the proper muscular walls of the body; mouth opening on the ventral surface of the snout in front of the commissures of the ganglia. a. Amphiporinoe. Proboscis proportionally large. These animals as a whole have comparatively short and thick bodies, 2 muscular layers in the body wall, an external circular and an internal longitudinal; the proboscis is composed of 3 divisions, the anterior having 7 coats, the middle bearing the stylets, the posterior forming a long sac with 2 muscular coats; 3 great longitudinal vascular trunks, 2 lateral and 1 median, besides a cephalic arch; the cephalic sacs or glands are accompanied by long tubes or ducts. 1. Amphiphorus, Ehrbg. Eyes more or legs numerous and large, but never arranged in a square. Body rather short, sometimes flattened; A. lactifloreus, Johnst., p. 156, pl. i. figs. 1 & 2; A. pulcher, J., p. 158, pl. i. fig. 3, & xiv. fig. 11; spectabilis, Qu., p. 160, pl. iii. figs. 2, 7 &8; hastatus, p. 162, pl. viii. fig. 2, and bioculatus, p. 163, pl. viii. fig. 3, spp. nn. (Shetland). 2. Tetrastemma, Ehr. Eyes 4, arranged so as to indicate a equaro or oblong. T. melanocephala, J., p. 165, pl. ii. fig. 1; robertiana, sp. n., p. 166, pl. iii. fig. 1; Candida, Mull., p. 167, pl. ii. figs. 2 & 3; rermicula, Qu., p. 169, pl. iii. fig. 3; flavida, Ehr., p. 170, pl. iv. fig. 1 ; dorsalis, Abgd., p. 172, pl. i. fig. 4, & iii. fig. 4. 3. Prosorrhochmus, Kef. Eyes 4, not forming a square; snout dimpled and furnished with a transverse superior lobe ; ovo-viviparous. C. claparedii, Kef., p. 174, pl. ii. fig. 4. b. Nemertinea. Proboscis proportionally small, the anterior region especially being shortened, so as to cause the stylet to approach the ganglia. Body more or less elongated; in other respects with the characters of the Amphiporinoe. 4. Nemertes, Cuv. N. gracilis, J., p. 176, pl. ii. fig. 5; neesi, Orst., p. 178, pl. iii. fig. 6, and pl. vii. fig. 6 ; carcinophila, Koll., p. 180, pl. i. fig. 5. B. Anopla. Proboscis without stylets. Nerve trunks generally placed between the muscular layers of the body wall. The mouth opens on the ventral surface behind the commissures of the ganglia. The blood-vessels aro somewhat less differentiated than in the Enopla, The young in the most conspicuous families undergo a remarkable metamorphosis. II. Lineidoe. Ganglia more or los
