QUARTERLY CHRONICLE. 49 



secrete only a thick liquid, others produce bundles of bacilli 

 in their interior, others, again, secrete granules. The bacilli- 

 parous follicles have been described by M. Claparede (who 

 compares them to cells filled with aciculee in Turbellaria, 

 and to Nematophores) and by other authors in very many 

 genera. They are not mentioned by de Quatrefages. 



The muscular tissue varies very much, being sometimes 

 simply fibrous, sometimes nucleated, and sometimes an un- 

 fibrillated protoplasmic mass, with scattered nuclei. M. 

 Claparede promises details on this subject. 



The perivisceral cavity is in some cases throughout lined 

 with cilia, but by no means always ; certain points, such as 

 the segment organs, being often the only ciliated parts. The 

 ciliation is stated, as a rule, to be general only in those 

 genera which have no vascular system. 



The following are anangian Annelids : — All the Aphro- 

 ditea (except A. aculeata), Glycerea, Polycirrida, and 

 Tomopteridea. The existence of blood-corpuscles in the 

 vessels of certain Annelida is now-a-days indubitable. In 

 Glycera the red corpuscles are floating in the perivisceral 

 cavity, no vessels existing (hence a condition very similar to 

 that of a Vertebrate is brought about), and Phoronis is 

 denied a place among Annelids by M. Claparede. The true 

 cases are to be found among the Syllidea, in the Opheliea, 

 the Cirratulea, and Staurocephalse. 



M. Claparede promises some important details on the 

 generative glands and segment-organs. He maintains that 

 a connective-tissue framework and vascular supply can 

 always be detected as the origin of the ova and sperm-cells. 

 Figures of segment-organs from many species will be given. 

 In some genera they are represented by apertures. Their 

 functions may be partly educatory of generative products 

 and partly excretory. 



The structure of the nervous system has also been carefully 

 investigated, and a follicular arrangement such as that 

 described by Leydig in the Hirudinea, observed in many 

 genera. The terminations of the nerves both in organs of 

 sight and hearing, and tactile corpuscles, is very fully to be 

 entered upon. Victor Carus is wrong in stating in his 

 ' Handbuch' that nearly all Annelida have auditory capsules. 



Reniarkable observations on the regeneration of lost parts 

 are referred to. In many cases M, Claparede has no doubt 

 that the anterior region, both head and many succeeding 

 segments, is reproduced. 



Altogether from his own account of it, M. Claparede's 



VOL. VIII. NEW SER. D 



