ZOOLOGY AND BOTANY, MICROSCOl'Y, ETC. 287 



describes the histology and rehitions of the structure, and inclines to 

 regard it as a superadded joint of the tarsus, perhaps connected with 

 tlie presence of internal claws. 



Meromyza saltatrix and Elachiptera cornuta.* — Prof. K. Linde- 

 man gives an account of the life-history of these two destructive 

 Dipt^Ta. The larva of Meromyza saltatrix is white with green shining 

 through ; the supports for the cephalic stigma are short and fungi- 

 form; the knob-like end contains seven terminal tracheal tubes which 

 open on some low warts ; the two cephalic hooks are large, black, 

 and armed inferiorly with two large blunt teeth. The puj)a is almost 

 colourless and distinctly constricted ; this stage is only of a fort- 

 night's length, and the whole period of develoijmeut not more than 

 seven weeks. The imago, when it first appears, is almost colourless 

 also, but soon becomes completely coloured. The larva of Elachi- 

 ptera cornuta has a remarkable resemblance to those of Oscinis, but 

 differs in the form of the supports for the cephalic stigmata, while 

 the cephalic hooks are markedly serriform. 



Parthenogenesis of Chironomus Grinimii.j — Prof. A. Schneider 

 confirms the discovery of Grimm as to the parthenogenesis of a 

 species of Chironomus. The larvje live as usual in tubes formed 

 from the secretion of the spinning gland, plus sand-grains and 

 portions of plants. At the periods of skin-casting the tube is shortened 

 and closed. In the imago within the larval envelope the sexual 

 organs are well developed, and the eggs are laid immediately after, 

 and occasionally before liberation, but only by the imago and not by 

 the pupa, as Grimm stated. The eggs are laid via the vagina, and 

 not, as in Grimm's account, via two lateral elliptical openings on 

 the posterior part of the body. 



Immediately after the eggs are laid, they begin to develope, and 

 even in some cases when artificially removed from the ovary. No 

 males were to be seen, and the receptaculum seminis was always 

 empty. Such parthenogenetic generations succeed one another through 

 the whole winter, and on till the middle of June. It is probable that 

 males are developed in summer and that fertilization then occurs. 

 Schneider differs from Grimm as to the development of the ova and 

 ovaries, but a discussion of this is reserved to a future communication. 



New Parasite on Iiilus.| — Dr. E. Haass describes a larval 

 parasite found by him (in 1880-81) on the head of Lilus fallax. 

 The yellowish- white oval egg measured 1 • 2 mm., was superficially 

 hexagonally marked, and fastened anteriorly very closely to the 

 lulus, while the posterior pole of the lower surface exhibited a 

 shallow, round, sucker-like hollow. Two larval forms were observed, 

 of an obviously insect character ; the first very young, with about 

 tw^elve segments, with much yolk still persisting ; the second derived 

 from the first by a skin-casting, covered with the short triangular spines 

 characteristic of Diptera, with little persistent yolk and with well 



* Bull. Soc. Impe'r. Moscou, Ix. (1S85) pp. 251-5. 

 t Zool. Beitr. (Schneider), i. (1885) pp. 301-2. 

 X Ibid., pp. 252-6(1 pi.). 



