ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 575 



Annulata. 



Change of Sex in Ophryotrocha puerilis.* — F. Braem halved a 

 female with ripe eggs. The head portion with thirteen segments was 

 isolated. In three weeks it had regenerated seven segments with para- 

 podia. It was then killed, and found to be male. The ova had dis- 

 appeared from the gonads, leaving only a residue, and a functional 

 testicular portion had developed, and was producing spermatozoa. 

 Braem thinks that in consequence of the amputation the very young, 

 indifferent germ-cells had developed into male cells, which require less 

 subsistence than ova. There was no trace of hermaphroditism to start 

 with. What is certain is that the gonads changed from producing eggs 

 to producing sperms. 



Artificial Parthenogenesis in Aricia.f — K. Kostanecki subjected 

 eggs of this Annelid for a short time to acid solutions (acetic or nitric), 

 and then to hypertonic solutions. A certain number of the eggs seg- 

 mented into three or four blastomeres, and a few reached the six- or 

 eight-cell stage. 



Littoral Polychseta of Torquay. £ — E. Y. Elwes reports on Phyllo- 

 docidre, JSephthyidae, Hesionidas, and Nereidse collected at Torquay, and 

 gives a useful key to the genera found on the French and English coasts 

 of the Channel. 



Development of Echiurus.§ — W. Salensky continues his study of 

 the development of the larva of Echiurus, giving particular attention to 

 the differentiation of the mesoblast and mesenchyme, and the formation 

 of the food-canal. 



Mediterranean Chsetognatha.jl — R. von Ritter-Zahony deals with 

 the Chajtognatha of the Eastern Mediterranean. He pays particular 

 attention to the question of vertical distribution, to the classification, 

 and to the detailed structure of the head. Details are given as to the 

 muscular strands, the teeth and the hooks, the nervous system, and the 

 gonads. 



Australasian Oligochaeta.lf — E. J. Goddard describes from New 

 South Wales two speeies of a new genus — Astacopsidrilus— of fresh- 

 water Oligochseta. The specimens were found in association with the 

 large crayfish (Astacopsis serratus). The new genus resembles Phreodilns 

 Beddard and PhreodrUoides Benham in general characters, but differs 

 from them in having spermathecal structures in the 14th segment, almost 

 devoid of musculature, without direct openings to the exterior, but 

 communicating with ovisacal structure in the 13th segment. 



The author also describes ** immature specimens of a Tasmanian 

 worm not unlike Phreodrihis maniensis. 



* Anat. Auzeig., xxxiii. (1908) pp. 19-27 (2 figs.). 

 t Bull. Internat. Acad. Sci. Cracovie, 1909, pp. 238-53 (16 figs.). 

 X Jouni. Mar. Biol. Assoc, viii. (1908) pp. 347-58. 



§ Bull. Acad. Imp. Sci. St. Petersbourg, ser. 6, i. (1909) pp. 363-80 (11 figs.). 

 || Denkschr. Math. Nat. Klasse Akad. Wiss. Wien, lxxxiv. (1908) p. 1-18 (lpl) 

 t Proc. Linn. Soc. N.S. Wales, xxxiii. (1909) pp. 768-93 (3 pis.). 

 ** Tom. cit., pp. S15-53. 



