ANNELIDES. 
287 
The following Irish Annelides have been enumerated by Thompson 
(Ann. Nat. Hist. vii. p. 482) : — N emeries gracilis, Johnst. ; Nem. lacti- 
fiorea, Johnst. ; Phylline hippoglossi, Lam. ( Hirudo Jiippoglossi, Miill.) ; 
Carinella trilineata, Johnst. ( Gordius annulatus, Mont.) ; Glossipora 
tuberculata, Johnst. 
Rathke has added a new species to the very little known family of 
Nemertince, which he has named Borlasia striata (Neuest. Danz. Schrif. 
p. 93). It was discovered on the coast of Norway. It is about the 
thickness of a crow-quill, and a foot in length ; the body is almost 
round, narrowed posteriorly, and marked with black stripes, alternating 
with twelve clearer ones. At the anterior margin of the body a small 
opening was found, which Rathke did not regard as the mouth, which 
lies farther down on the abdominal side, and represents a large longitu- 
dinal cleft. On the right and left of the anterior end of the body is a 
boat-shaped, superficial, longitudinal furrow, to which a strong bundle 
of nervous fibres passes from the red ganglion of the brain, on which 
account Rathke is inclined to think these furrows are the seat of more 
acute sensation. Before them, eight or nine very small black ocellated 
points are observable. The slimy thickish cuticular covering has a num- 
ber of slight segmental furrows. The intestine, running out straight at 
the posterior end of the body, contained a whitish slimy fluid, from which 
Rathke conjectures, that this worm sucks its nourishment from other 
white-blooded animals. As a great number of small, thin, cuticular 
sacs, which were attached in a single row, behind each other, on the 
inner wall of the body of this worm, contained in some individuals dis- 
tinct eggs, and in others a fine granular substance (semen), Rathke 
assumed, that it possessed separated sexes; but he could not discover 
sexual openings in these sacs. Under the dorsum runs a very long 
snow-white and spiral canal, which is very muscular, and can be bulged 
out, like a proboscis, at the opening first mentioned. He could not make 
out its use. It does not belong to the sexual parts, as very young spe- 
cimens, which had neither sexual bladders nor testes, yet possessed this 
organ. The abdominal nerve of this worm is composed of two white 
cords, which, arising from the ganglion of the brain, run down on the 
lateral margin of the body, far separate from each other, without 
forming ganglions. Other Naturalists do not agree with this view of 
the organs. Dr. G. Johnston takes the two nervous cords for blood- 
vessels, and the cerebral ganglion for a heart. Ehrenberg holds the 
alimentary canal to be an egg passage, and the white spiral organ is, he 
thinks, the intestinal canal; while Huschke takes the latter for a se- 
minal vessel, and the bulged-out proboscis for the penis. The researches 
of Quatrefages (ITnstitut. p. 427, 1841) agree better with those of 
Rathke. He describes the nervous system of Nemertes as two long- 
threads, running down on both sides of the body, which arise from two 
331 
