ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
47 
Prof. J. H. Comstock* and Dr. T. A. Chapman.f The former has dis- 
covered that the fore and hind wings of the Hepialidse and the Micro- 
pterygidae are united by a membranous lobe which he calls the “ jugum ” ; 
this jugum is found also in the Trichoptera. As it has long been recog- 
nized that these two families of Lepidoptera are widely separated from 
all the others, and that, further, they have very different mouth-organs 
the one from the other, this discovery of a specialized common structure 
is of great importance. The possession of a jugum by the Trichoptera 
is a strong argument in favour of the derivation of the Lepidoptera 
from that group, and against the theory of a Hymenopterous ancestor. 
Dr. Chapman’s discovery of the larva of Eriocephala — the lower of the two 
Micropterygid genera — tends to complete our knowledge of the group. 
Suggestions are made as to a revised arrangement of the families of 
Lepidoptera. 
Classification of Lepidopterous Larvse.J — Mr. H. G. Dyar finds 
that a classification based on the structure and arrangement of the 
setiferous tubercles corroborates in a general way Comstock’s classifica- 
tion based on the methods of union between fore and hind wings and on 
the modifications of the wing veins. That there should not be perfect 
agreement is natural when we remember that larvae living an exposed 
life show many particular specializations. There are two great types of 
arrangement. The first or more generalized shows, in the abdominal 
segments, five tubercles above the spiracle on each side, three in a trans- 
verse row about the middle of the segment, and two behind, and two 
oblique rows below the spiracle with two and four tubercles respectively. 
The second type shows on each side above the spiracle three tubercles ; 
below, or behind the spiracle and above the base of the leg, three more ; 
on the base of the leg three (or four) on the outside and one on the 
inside near the mid-ventral line. Mr. Dyar’s classification of larvae is 
based on the modifications in these fundamental arrangements and in 
the tubercles themselves. 
Spermatogenesis of Silk Moth.§ — Prof. E. Verson returns to his 
investigation of the spermatogenesis of Bombyx mori , as his previous 
work (1889) has been partly overlooked, partly misunderstood. The 
kidney-shaped testis consists of four chambers, the narrowed ends of 
which open into a common vas deferens. In each chamber, near the 
outer margin of the testis, there is a giant cell whose margin is notched 
and fringed, with small roundish nucleated elements between the 
radiating strands. There is no evidence of an epithelium covering 
each chamber nor of division into special follicles, as is alleged in other 
Lepidoptera. Each capsule consists of connective tissue, and tracheae 
extend freely into its cavity. The spermatogonia of v. La Valette 
correspond to the nuclei around the margin of the giant cell, but what 
Verson insists upon is that the giant cell embraces and nourishes all 
the specific elements of a chamber, and connects the spermatogonia and 
their products the spermatocysts. The nucleus of the giant cell divides ; 
nuclei have been seen in transit outwards to the radiate periphery ; 
* Wilder Quarter Century Book (1893) pp. 37-113. 
t Trans. Ent. Soc., 1893, p. 97, and 1894, p. 335. 
X Ann. N.Y. Acad., viii. (1894) pp. 194-232 (6 figs.). 
§ Zcitschr. f wiss. Zool., lviii. (1894) pp. 303-13 (1 pi.). 
