502 Miscellaneous. 



Peristeropode, still less to a Talegalla or a Megapode. Prom this 

 negative result we may, I will not say assert, but at least suppose 

 that at that distant epoch this remarkable type of Gallinaceae was 

 already foreign to Europe, and was confined to the Indo-Australian 

 region. — Comptes Rendus, April 19, 1880, p. 906. 



On the Structure of some Coralliaria. By H. C. Meeejkowsky. 



Among the Coralliaria, the Actiniae especially have been the best 

 investigated. The almost total deficiency of facts relating to the 

 microscopic structure of the other groups decided me to undertake 

 a special study of some species common in the Bay of Naples, such 

 as Astroides &c. The following are the results at which I have 

 arrived. 



The ectoderm, examined by means of sections and of maceration, 

 proved to be composed of the following elements : — 



1. Ordinary ectodermic cells of very elongated form, strongly 

 depressed and dilated at the superior extremity, which is constantly 

 furnished only with a single oiliuin. In this respect the ectodermic 

 cells of Astroides are very notably distinguished from those of the 

 Actinia? described by M. Heider, which have always several very 

 short cilia. 



2. The preceding cells, but with this difference, that they become 

 transformed at their base into an excessively long and delicate fila- 

 ment, sometimes furnished with several inflations, which our know- 

 ledge of the group of the Ccelenterata authorizes me to call nervous 

 filaments. 



3. Epithelio-muscular elements composed of cells no. 1 (more 

 normal, that is to say shorter and broader) united at their base to 

 muscular fibrillae. This kind of element is not, however, so fre- 

 quently met with here as in the endoderm; at their apex there is 

 always a long cilium. 



4. ISTematocysts of two kinds : larger ones, often surrounded by 

 protoplasm, with a nucleus and a long filament (nervous) in the 

 posterior part ; the others smaller, of a different form, and always 

 provided with a long posterior filament ; the filament here and 

 there bears small nodosities. 



5. The last elements of the ectoderm are the glandular cells, 

 always pyriform and with coarsely granular contents. 



Mesoderm. — The elastic and structureless membrane which sepa- 

 rates the ectoderm from the entoderm varies in thickness in the 

 different parts of the body ; it forms longitudinal protuberances 

 upon the faces of two mesembryenthal septa which unite at the 

 surface of the stomach. The muscles which line this elastic mem- 

 brane in a single layer are longitudinal in the interior of the 

 animal, and arranged in horizontal circles at the exterior. They 

 are either long slightly flattened filaments, the relations of which 

 to the other histological elements it is not easy to ascertain, or they 

 are fibrillar forming a part of the epithelio-muscular elements. 



We must also mention another very curious element, consisting 

 of cells of comparatively large size and exceedingly flattened, much 



