ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 439 



As to the function of the " brown body," Dr. Vigelius is not quite 

 in accord with Joliet, but considers its function to be one of nourish- 

 ment, for in it, so to say, nourishment is preserved which during tho 

 absence of an intestine is at least partly assimilated by the animal. 



The ovicells which have previously been examined were all 

 external, whereas in this Flustra they are internal, but upon ex- 

 amination the difference was not found to be so extreme as at first 

 sight appeared. The cover of the ovicell chamber is closed by two 

 extremely delicate muscles. It is thought that probably the larva- 

 sack in Alcyonella is to be compared morphologically with the 

 concealed ovicells of the Chilostomata. 



The existence of a nervous system is still an open question, but 

 the author considers that possibly a cluster of round or polygonal 

 cells with large nuclei may be nerve-cells, and as the position is the 

 same as that of the nerve-centre in the Entoprocta, the idea thus 

 receives considerable support. 



As the different walls of the zooecium have been variously desig- 

 nated by different naturalists, it would be well if the names proposed 

 by Dr. Vigelius could be generally adopted. The "opercular wall " 

 has been called the front, htemal side, the " bauchseite," and the upper 

 side ; the " neural wall " has been known as the dorsal or lower wall ; 

 the others are the distal, proximal, and lateral walls. 



TJrnatella gracilis.* — Prof. J. Leidy describes some specimens of 

 Urnatella gracilis, which nearly all consisted of two stems of unequal 

 length and devoid of terminal polyps. In March the stems had all 

 developed polyps at the distal end. Most were terminated by a 

 single polyp, but a few had also a smaller one on a cylindrical joint 

 springing from the antepenultimate joint of the stem. If portions of 

 the stem are destroyed, the remaining joints are capable of reproducing 

 the polyps. Branches usually spring from the last one or two joints, 

 newly produced from that which immediately supports the terminal 

 polyp. Heads may start laterally from old or mature joints. Thus 

 the latter apjiear to serve as the statoblasts of other fresh-water 

 polyzoa, but ordinarily they do not become isolated from one another. 



New Polyzoa.t —In continuation of his " Contributions towards a 

 general history of the Marine Polyzoa," the Eev. T. Hincks describes 

 some new Cheilostomata from New Zealand and Australia. Of the 

 genus Diaclioris two new species (and two others) are described, in 

 which the avicularia present remarkable features : there are besides 

 three new species of Memhranijiora, two new forms of Microporella 

 Malusii Aud., and M. diadema MacGill. Four new species (and 

 two others) of Sckizoporella ; a specimen doubtfully referred to 

 nippothoa which bears a very close resemblance to H. expansa, aud 

 which exhibits some curious secondary cells (?) ; also three new 

 species (and one other) of Lepralia. 



* Proc. AcaJ. Nat. Sci. Pliilad., 1884, p. 282. 



t Aim. and Mag. Nat. Hist., xv. (.1885) pp. 244-57 (3 pis.). 



