42 REVIEW. 
subjects of circulation and respiration are discussed very 
fully. The researches of Milne-Edwards were the first in 
elucidating this portion of the anatomy of the Annelida; and 
it almost seems to have become specially appropriated to the 
investigation of French naturalists. 7. Organs and func- 
tions of secretion—Under this head the abundant secretion 
of viscid material from the skin, such as is observed in 
Lumbrinereis, Cirrhatulus, Chetopterus, and all tube-build- 
ing forms, is briefly discussed. 8. Organs and functions 
of innervation—The nervous: system is described as con- 
sisting of a general and a visceral system, the first comprising 
the “ brain,” or large bifid supra-cesophageal mass and the 
ventral chain of ganglia; the second of a chain or series of 
stomato-gastric ganglia, variously modified in the different 
genera. 9. Organs of the senses.—The sense of touch is very 
briefly passed over, very little being said as to the sensitive 
papille and hair-like appendages of some Annelids. The 
author inclines to the belief that the Nereides possess the 
sense of taste, from the structure of the pharynx, but no 
evidence is adduced from other Annelids. The organ of 
hearing, first recognised by Grube and Siebold in Arenicola, 
is considered by M. de Quatrefages the only well-attested 
example of such a structure in Annelida. Carus, however, 
in his ‘ Handbuch ’ (1864) regards all Annelids as possessing 
such organs. M. de Quatrefages says he has twice observed 
some such organ in Eunice sanguinea, but he does not feel 
sufficiently certain of its nature. The eye is well developed 
in many Annelids, as the researches of Muller, Wagner, 
Rathke, Siebold, and chiefly M. de Quatrefages himself, 
attest. The curious genera Amphicorine and Polyophthalmus, 
the one with eyes at the tail, the other with an eye to each 
ring of the body, are refigured and described. 9. Organs 
and functions of locomotion.—The explanation offered of 
the mode of action of the feet in those Annelids in which 
they are developed as locomotory organs is worth notice. 
A .very large share of importance is ascribed to the fluid 
of the general cavity, in relation to locomotion. It acts 
by distending the erectile tissue of the feet, and also stiffens 
each part of the body successively in a similar manner, thus 
giving a point d’appui to the muscles which are attached to 
those parts. 11. Organs and functions of generation.—'The 
different subjects coming under this head—ovaries, sperma- 
tozoa, accessory organs, &c.—are treated at some length. The 
modifications which the embryo undergoes, andthe subsequent 
phenomena of alternating generation, or geneagenesis, as M. 
de Quatrefages calls it, are discussed as far as the facts at 
