Bibliographical Notices. 121 



ring upon his genera the most unhappy names. Laguncula, it 

 appears, is to be considered the euphonious diminutive of Lagena ! — 

 his Hydraciinia has little relationship either to Hydra or Actinia, 

 and is most certainly not the link of connexion betM^een them : — and 

 lo ! we have now a Sompocellaria, — certainly the ugliest of this ugly 

 family. 



The anatomy of the Laguncula is well-described and beautifully 

 illustrated, but does not present much novelty to those who are 

 familiar with the labours of Dr. Farre. We shall cull what strikes 

 us as most peculiar to the author. 



The inner surface of the stomach is furnished with a semilunar 

 series of ciha, by whose vibrations the food is kept in a continual 

 rotatory motion. There is no appearance of a liver. 



The tentacula are the principal organs of respiration : they vary 

 in number — 10, 11 or 12, and this variation is not the result of 

 mutilation. The circle they form is less regular than that of other 

 marine Bryozoa, for they are disposed in a symmetrical order, and 

 give indication of the beginning of a binary disposition. Laguncula 

 may therefore be considered as a link between its marine congenera 

 and the freshwater Hippocrepia of Gervais. 



The purpose of a circulation is eflFected, but without the agency 

 of special organs. A col^ourless transparent fluid, loaded with irre- 

 gular globules of comparatively large size, fills the space between 

 the intestinal canal and the skin, and lies in immediate contact with 

 all the organs of the polype. It thus occupies a position like to 

 that of the blood in the superior animals ; and although the liquid 

 seems to be water merely, it distributes to each part of the body its 

 nutritive element, and hence also fulfils the same function as the 

 blood does. We cannot perceive any aperture for the admission of 

 the circumfluent water into the peri-intestinal cavity, but Van Bene- 

 den is assured of its existence, for he had seen an ^^g issue forth 

 through the walls of the cell when no pressure was used to force it 

 out. And yet, when these polypes were immersed for a night in 

 water coloured with carmine, the peri- intestinal fluid remained 

 untinctured. Lastly, this fluid has the same ofiSce in the system as 

 the prostatic secretion (le liquide du sperme), for both spermatozoa 

 and ova swim freely in it. [There is here surely a painful search 

 after analogies, which, after all, appear to us to be of the very loosest 

 kind.] 



M. DuMortier first discovered a nervous system in polypes. Van 

 Beneden has seen it in this genus. A transparent, somewhat yel- 

 lowish ganglion on the top of the oesophagus, and as it were soldered 

 to its parietes, may be seen in some specimens and in certain favour- 

 able aspects ; but Van Beneden could not detect any collar or nerves 

 branching from the ganglion, while at the same time he considers 

 their reality to be indisputable. The ganglion is assumed to be ner- 

 vous from the sameness of its position to the brain of the Ascidia. 



We pass over the excellent description given of the muscular 

 system, of the skin and cell, to notice some particulars of the repro- 

 ductive organs. The polypes are hermaphrodites, there being a 



Ann. ^ Mag. N. Hist. Vol xvii. K 



