ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 551 



Roscoff and Arcachou without any success, but found the red corpuscles 

 in specimens from Naples. It turns out that the species so named at 

 Naples is really Pectmiculus violascens Lam. 



Arthropoda. 



Epithelial Regeneration in Mid-gut of Arthropods. * — L. Leger 

 and 0. Duboscq have studied the mitotic regeneration of the epithelium 

 in Decapod Crustaceans, in Lithobius, and in various insects. In general 

 their results confirm the theory of Ziegler and Vom Rath of variously 

 distributed loci of regeneration where mitosis occurs. 



Collection of Microscopic Marine Arthropods, f — E. Trouessart 

 gives directions in fourteen paragraphs in regard to the collecting of 

 minute Halacaridae, Crustacea, &c. iu marine exploration. We cannot 

 condense them, but the reference may be of service to explorers inte- 

 rested in having a complete survey. 



o. Insecta. 



General Course of Entomology.!— J. H. Comstock and V. L. Eellogg 

 have published a new edition of a work that " represents the fundamental 

 laboratory course in the chief centre of entomological instruction in 

 America." J. G. Needham, in reviewiug it, says : " For a simple, 

 straightforward, condensed guide to the laboratory study of elementary 

 insect anatomy, there is no such book elsewhere." 



Habits of Larvae of Sciara medullaris.§ —A. Giard has studied the 

 habits of these larvae, which are very common on the dried stems of 

 Senecio jacobsea at Wimereux. They feed on the pith of the ragwort, 

 and there was no evidence of a diet of animal matter, as is sometimes 

 described. Like some other Dipterous larvae (Syrphidae), they have a 

 marked power of surviving desiccation. If a piece of stem containing 

 them be dried in a warm chamber, the larvae become inert, and develop- 

 ment stops ; when the stem is rejilaced in a moist chamber, after three 

 weeks or more the larvae return to their normal activity. They are 

 positively hydrotropic, but at the approach of pupation the hydro- 

 tropism becomes negative. The gregarious instinet, more marked in the 

 army-worm, Sciara militaris, is briefly discussed, and further evidence 

 is given of the extent to which the habits are dominated by the con- 

 ditions of humidity. 



Expulsion of Spermatozoa in Sciara.||— A. Giard has a remarkable 

 story to tell of the genesis, liberation, and behaviour of the spermatozoa 

 in this Dipterous iusect. The phenomena of emission are as compli- 

 cated as in Hirudinea and Cephalopoda, though there is not, in the 

 strict sense, any spermatophore. The " synandry" or aggregation of 

 the spermatozoa, is especially remarkable. 



Studies on Ants.f — Adele M. Fielde continues her study of ants, 

 and finds that Stenamma fulvum piceum is the bearer of three distinct 



* Arch. Zool. Expe'r., x. (1902) Notes et Revue, pp. xxxvi.-xlii. 

 t Bull. Soc. Zool. Fiance, xxvii. (1902) pp. 23-7. 



X The Elements of Insect Anatom)-, Ithaca, 1901, 8vo, 145 pp. and 11 figs. See 

 Amer. Nat., xxxvi. (1902) pp 500-1. 



§ Conaptes Rendus, cxxxiv. (1902) pp. 1179 85. . || Tom. cit., pp. 1124-7. 

 i Froc Acad. Sci. Philadelphia, 1901, pp. 521-44 (2 figs.). 



