588 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
the partially reticular fatty -body arises from the gradual vacuolation 
of oenocytes. Groups of these oenocytes occur in the eight anterior 
stigma-bearing segments of the abdomen. They arise from a prolifera- 
tion and subsequent delamination of the ectoderm. Furthermore, in 
Hydrophilus, Graber has discovered that the parastigmatic groups of 
oenocytes arise in a hitherto unobserved fashion by an invagination of 
the ectoderm, which is, however, associated with a proliferation and 
delamination. 
Signs of Copulation in Insects.* * * § — Prof. F. Leydig has collected, 
partly from his own observations, partly from those of others, a number 
of cases in which female insects bear traces of copulation, in the form of 
tags or plates attached to the body, and apparently formed from material 
secreted by the male. Such probably is the “ pouch ” on the abdomen of 
Parnassius Apollo , and a somewhat similar structure in Fulgora later- 
naria, and such is the plate which is found on the posterior abdomen of 
Dytiscus latissimus and D. marginalis. Leydig compares these things 
with the white plate in Astacus fluviatilis, and with a little white lid on 
the spider Argenna , and finds analogues among Vertebrates. 
Morphology of Lepidoptera.f — In the first of his communications 
under the above title Mr. W. Hatchett Jackson deals with two subjects — 
the external anatomical marks by means of which the sex of a chrysalis 
may be determined, and the mode in which the azygos oviduct or vagina 
of the female butterfly with its accessory organs developes between the 
close of larval life and the assumption of the imago-state. As we gave 
a full account of the preliminary notice of his results J we must, in 
calling attention to their publication, confine ourselves to one or two 
points. It would appear that, in Germany, some “practical Lepi- 
dopterists ” were able to discriminate the sexes of Lepidopteran 
chrysalids, though none in England did so before Mr. Jackson’s work 
became known. Some experiments on colour-variation which were 
undertaken by the way seem to bear out the conclusions of Poulton. 
The anatomy of the genital ducts in the Microlepidoptera should be 
studied as it may bring to light transitional or primitive stages, just as 
Walter’s researches have clearly shown that a primitive biting condition 
of the mouth-parts exists in some of them at this day. 
Morphology of Lepidopterous Pupa.§ — Mr. E. B. Poulton, in 
describing the morphology of the lepidopterous pupa, discusses its 
relation to that of the other stages and to the origin and history of 
metamorphosis. He points out the error of naming the various appen- 
dages and other organs of the pupa as if they were mere cases for the 
corresponding parts of the imago ; the appendages or organs are parts of 
the pupa, and should be spoken of as such ; they are far more ancestral 
than the imaginal organs, and are remnants of a time when the last stage 
of metamorphosis in the ancestors of Lepidoptera was something very 
different from a butterfly or moth ; the fault of the old terminology w r as 
that it obscured the fact that the pupa has a morphological meaning of 
* Arbeit. Zool.-Zoot. Inst. Wurzburg (Semper), x. (1891) pp. 37-55 (2 figs.). 
t Trans. Linn. Soc. Lond., v. (1890) pp. 143-86 (5 pis.). 
j This Journal, 1890, p. 29. 
§ Trans. Lilin Soc. Lond., v. (1890) pp. 187-212 (2 pis.), 245-63 (2 pis.). 
