ZOOLOGY AND BOTANY, MIOBOSOOPY, ETO. 
319 
Plymouth Hydroids.* — Prof. 0. C. Nutting has some notes on these, 
describing Eudendrium album sp. n., Opercular ella hispida sp. n., Plumu - 
laria Alleni sp. n., &c. In discussing Plumularia pinnata , the author 
deals particularly with the nematophores. Each consists of a “ sarco- 
style ” — the sarcodal process, and a “ sarcotheca ” — the chitinous 
receptacle. One pair of naked sarcostyles is found in the usual position 
of the supracalycine nematophores, and another pair is in the axil of 
each hydrocladium. The greater part of the sarcostyle is composed of 
ectodermic cells ; there is a central endoderm core, with a cavity in one 
species ; the cells on one side of this core are very large and quad- 
rangular ; there are pseudopodia-like processes from the free surface of 
the sarcostyle. No free interstitial protoplasm, as described by Merej- 
kowsky and Weismann, was observed. As to function, it seems that in 
P. pinnata the sarcostyles are primarily neither fighting persons, nor 
concerned in the repair of mutilated or diseased parts. It is probable, 
on the other hand, that they remove extraneous matter, or dead organic 
material from the interior of the hydrothecm and gonangia, and that 
they may aid in the capture and ingestion of food for the colony. As 
Weismann showed, both ova and spermatoblasts arise in the endoderm of 
the stem, and migrate to the gonophores. The ova break through the 
Stutz-lamella , and are fertilised and segmented between this and the ecto- 
derm. The primary divisions of the spermatoblasts occur in the endo- 
derm. An unusual mode of asexual reproduction, by what may be called 
stolons, is described in the same species. 
Porifera. 
Growth of Sponges.f — Messrs. E. J. Allen and G. Bidder have 
made an interesting report on the possibilities of the artificial culture 
of sponges. Buccich concluded that sponge-cuttings would grow to 
marketable size in seven years, and the Florida experiments seem to 
show that a piece may, in favourable conditions, grow to 4-6 times the 
original size in six months. Marenzeller points out, however, that there 
is lack of evidence that cut pieces of a sponge would, in a given time, 
together attain a greater weight than the original sponge would have 
reached if left undisturbed. Mr. Bidder also says there seems to be no 
reason to suppose that the yield of a sponge fishery will be increased by 
planting cuttings, unless these are placed in more advantageous positions 
than the original sponges. He suggests attaching either cuttings or 
small sponges to canes or tiles, disposed on iron hurdles standing some 
feet from the sea-bottom. 
Protozoa. 
New Tintinnidse, t — Prof. K. Brandt describes some new Tintinnidse 
collected by Vanhofien in Davis Strait, Karajak Fjord, &c. s on the 
Greenland expedition. The new forms are four species of Tintinnus ; 
five species of Tintinnopsis ; Ptychocylis g. n. with four new species; 
and three new species of Cyttarocylis. 
Brandt also discusses the structure of the test. In Tintinnus , it 
* Journ. Marine Biol. Ass., iv. (1896) pp. 146-54. f Tom. cit., pp. 188-200. 
X Bibliotheca Zoologica (Leuckart and Chun), Heft 20 (1896) pp. 45-72 (1 pi.). 
z 2 
