ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
523 
phenomena beyond the reach of present experimental methods. The 
abnormality is not to be denied because it is past our limited under- 
standing. 
Spermatogenesis of Caloptenus Femur-Kubrum and Cicada Tibi- 
cen.* * * § — Mr. E. V. Wilcox has published a detailed account of his 
observations on these insects.f Degenerating cells are stated to be very 
frequent in the testicular follicles of Cicada. The first sign by which 
he was able to recognise that a spermatogonium is becoming abnormal was 
a chemical change in the nucleus, the chromosomes staining more 
brightly than in normal cells, while the cytoplasm becomes clearer and 
more homogeneous. The chromosomes next become irregular in shape, 
lose their individuality, and fuse into a single mass. In Cicada there 
are frequently seen spermatozoa and various stages in the metamorphosis 
of spermatids, which are four or five times as large as the corresponding 
normal forms. These may be called giant spermatozoa. These, the 
author believes, are not functional, but that they are excluded from the 
developmental series and that really they come to nought. He is not 
aware that any one has hitherto suggested that they arise directly from 
spermatogonia, and a priori it seems quite improbable, but the author’s 
Cicada preparations point very strongly to this conclusion. The whole 
history of spermatogenesis is so closely bound up with references to the 
figures as to make a detailed account of Mr. Wilcox’s observations quite 
impossible. In the latter part of his paper he enters into a useful 
critical account of what has been done by his predecessors. 
The Blow-Fly 4 — We can only call attention to the conclusion of 
the second edition of Mr. B. Thompson Lowne’s well-known work on 
this subject, which contains a large amount of original work, as well as 
discussions of the results of others. 
Bleeding of Coccinellid9e.§ — Herr K. G. Lutz summarises what has 
been recorded concerning the bleeding of Coccinellidae, and from his 
own observations comes to the following conclusions : — the blood issues 
through a cleft in the knee-joint, in the outer of the two membranes 
surrounding the tendons of the extensor of the tibia ; the bleeding 
follows a strong contraction of the posterior part of the body and of the 
flexor of the tibia, and is voluntary ; it is a means of defence, for the 
blood is repulsive to insectivorous animals. In Timarcha, Meloe , &c., 
the arrangements which secure the outflow of blood are probably the 
same as in Coccinellidae. 
“ Petiole” of Ants.|| — M. Ch. Janet finds that the waist or petiole 
of Myrmica rubra , which consists of the fifth and sixth post-cephalic 
segments, has all the organs — two longitudinal tracheae, the aorta, the 
gut and two gastric nerves, the nerve-cord and the musculature, &c. — 
in their usual relative positions. 
* Bull. Mus. Comp. Zool., xxvii. (1895) pp. 1-28 (5 pis.). 
t See this Journal, ante, p. 171. 
+ ‘ The Anatomy, Physiology, Morphology, and Development of the Blow-fly/ 
London, 1893-5, 2 vols. 8vo, 745 pp., 52 pis. 
§ Zool. Anzeig., xviii. (1895) pp. 244-55 (1 fig.). 
1! Mem. Soc. Zool. France, vii. (1895) pp. 185-202 (6 figs.). 
