114 E. RAY LANKESTER, ON THE 
consists of a corpusculated colourless fluid, contained in the 
somatic cavity, and provided with exits and a series of 
capillary canals for the entrance of liquid, and of a red- 
coloured, non-corpusculated fluid contained in three longi- 
tudinal trunks and their ramifications. Both are albu- 
minous ; the former is homologous with the blood of Insects 
and Crustacea, and probably performs a nutritive function ; 
the latter is homologous with the water- vascular system of 
Scolecida, and has an excretory or urinary function through 
the segmental organs, and a respiratory function, in connec- 
tion with the oxygen absorbed by the perivisceral fluid. 
The nervous system consists of a supra- and a sub-intes- 
tinal portion, both of which present the usual components 
of fibres and cells. The principal centre is the cephalic 
bilobed ganglion, homologous with the corpus callosum and 
the commissure prolonged throngh the corpora quadrigemina. 
From this in one direction pass the cephalic nerves, in the 
other the phargyngeal crura, uniting beneath the pharynx to 
form the subventral cord and ganglia. From the pharyn- 
geal crus four branches on either side unite to form the 
supra-intestinal chain or plexus discovered by Lockhart 
Clarke, and homologous with the sympathetic and visceral 
ganglia of mollusca. Four other twigs on either side are 
distributed to the pharynx. The muscles of the segments 
are presided over by the subventral cord. There are no 
special organs of sense, unless the labial segment should be so 
considered. 
BIBLIOGRAPHY. 
Borecx.—Om 7 Artsformer of Lumbricus terrestris iagttague 
i Norge; im ‘ Forhandlgr. skand. Naturforsk,’ 2 Mode 
1840, p. 273. 
Cuarrin.—Le Lombric terrestre, vulgairement appelé ver de 
terre. Sujet tiré au sort. Paris, impr. d’Apperl, 1852. 
Crarkeg, John Lockhart.—On the Nervous System of Lumbvi- 
cus terrestris; nm ‘ Proc. Roy. Soc. London,’ vol. viii, 
1856, p. 348—352. 
D’Uprexrem, Ful.—Developpement du Lombric terrestre ; in 
‘Mém. Cour. et Mém. d. Say. etrang. de l’Acad. de 
Belg.,’ tom. xxvii, 1856. Beneden P. T. van.—Rapport sur 
le Mémoire de M. Jul. D’ Udekem; in ‘Bull. de Acad. de 
Belg.,’ tom. xx, 3, 1853, p.357. Schwann, Th.—Rapport 
sur le méme Mém.; ibid., pp. 397, 398. Cautraine. The 
same, in ‘ L’ Institut,’ xxii, No. 1063, 1854, pp. 107—172. 
Durovur, Léon.—Notice sur les cocons ou les ceufs du Lum- 
