ZOOLOGY AND BOTANY, MICBOSCOPY, ETC. 35 



red staining', correspond mainly to the terminal saccule of the shell- 

 s-land, but that in some cases, e.g. in Daphnia, there is a rudiment of the 

 antennary gland. 



Annulata. 



Eye of Alciopa cantrainii.* — R. Demoll gives a detailed account 

 of the structure of the eye. and a discussion of its functioning. Among 

 the many points of interest we may note : (a) that there is here the 

 most primitive form of an optic chiasma ; (b) that there is in the middle 

 of the retina a spot of acutest vision ; and (c) that the Alciopid optic 

 ganglion should he compared rather to the retinal ganglion of Verte- 

 brates than to the optic thalamus. 



Artificial Parthenogenesis in Aricia.t — K. Kostanecki has induced 

 parthenogenetic segmentation in the eggs of Aricia by subjecting them 

 to acetic acid or nitric acid solutions, with subsecpient transference to 

 hypertonic solutions. Only a few of the ova segmented, and few got 

 beyond three or four cells. In some cases six and eight cells were 

 formed. The nuclear phenomena were carefully observed. 



Peruvian Polychsets.J — Ch. Gravier gives an account of a collection 

 made by Dr. Rivet at Payta on the Peruvian coast. Of the nineteen 

 species nine are new. Some of the extensions of distribution are 

 striking : thus Stijlaroides (Trophonia) capmsis Mcintosh previously 

 reported from the Cape and from the Red Sea, is now recorded from 

 Ceylon. 



Disease in ArenicolaJ — II. B. Fantham and Annie Porter note 

 that few pathogenic bacteria have been described from the digestive 

 tract of Invertebrates, and that it is, therefore, of interest to record 

 Bacillus arenicolse sp. n. from the lumen of the gut and within the 

 intestinal epithelium of Armicola ecaudata. The bacillus causes lesions 

 in the gut-epithelium, and may hasten the death of the Annelid. 



Blood-vessels of Australian Earthworms. || — Gwynneth Buchanan 

 has studied nineteen species of MeijascoUdes, Megascolex, Diporochaeta, 

 Perichseta, etc. The number of hearts seems to be fairly constant, three 

 being the usual ; they may be always distinguished from mere swollen 

 vessels by their connection with the supra-intestinal (except in Diporo- 

 chueta davallia) ; their function is mainly propelling. There is no 

 evidence in Australian forms of the existence of a subneural vessel. 

 The ventral blood-vessel is always single ; the dorsal is usually single. 

 The blood supply to the alimentary canal and related structures at 

 the anterior end is generally more or less in the form of a plexus. 

 These are a few of the points in this paper. 



Musculature of Hirudinea.^I — Louis des Arts has studied numerous 

 types. The element is the unicellular muscle-fibre, which has a con- 



* Zool. Jahrb'., xxvii. (1909) pp. 651-86 (1 pi. and 4 figs.). 



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



X Arch. Zool. Exper., x. (1909) pp. 617-59 (3 pis.). 



§ Centralbl. Bakt. Parasitenk., lii. (1909) pp. 329-34 (1 pi.). 



|| Proc. E. Soc. Victoria, xxii. (1909) pp. 59-84 (4 pis.). 



i Jenaisclie Zeitschr. f. Natunv., xliv. (1909) pp. 415-66 (3 pis.). 



