Page:The Zoologist, 3rd series, vol 1 (1877).djvu/296

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270
THE ZOOLOGIST.

Mauritius, about 360 miles distant), by Captain Raeburn, of the ship 'Airlie.' The moth is a common Indian species, but is found also in Africa. A specimen was long ago received from Brazil, and Mr. Grote had recently noticed its occurrence in Florida.

Mr. M'Lachlan also exhibited a cocoon and pupæ of a species of Cetoniidæ (probably Diplognathus silaceus) from Cameroons, sent to Mr. Rutherford. The cocoon appeared to be formed of dark brown earth, but attached thickly to the exterior were oval, slightly flattened, deep black, hard bodies (each nearly five lines long by two broad), which he thought were probably the excrement of some rodent quadruped.

Mr. Champion exhibited Stenus Kiesemwetteri (hitherto only found in this country at Wimbledon), Gymnusa brevicollis, Bembidium nigricorne, and Plociomerus luridus, all from Chobham; also Philonthus cicatricosus from Shoreham.

Mr. Howard Vaughan exhibited (on behalf of Mr. Bidwell) a specimen of Notodonta trilophus, taken about the year 1867 at Ipswich by a lamplighter. Mr. Douglas had captured some years ago at St. Osyth, in Essex, what was hitherto the only authentic British specimen of this insect.

The President read some interesting remarks from a letter he had received from Mr. B.G. Cole respecting some specimens of Ephyra punctaria which he had bred from eggs laid by the same female, the greater number of which emerged from the pupæ in July (as the spotted variety), while the remainder appeared in May, in all respects resembling the mother. He repeated the experiment in 1876 with similar results; all but one pupa from a batch of eggs laid in May appeared in July as the spotted form (males and females), the single exception remaining still in pupa, which it was presumed would appear during the coming May in the vernal dress. In this latter case he had reared a second brood of larvæ from eggs laid by some of the July females, all of which were now in the chrysalis state. Mr. Cole added—

"May not the above be considered a case of 'season-dimorphism' analogous to that occurring in Pieris, Araschnia, Selenia, &c., as investigated by Dr. Weismann, a slow process of development during the winter being necessary for the production of the May form (which may be considered the type), whilst if the development of the pupa is hastened by the heat (and light?) of summer, the smaller and less perfect individuals are the result. Referring to the similar case of Selenia illustraria, Dr. Knaggs (Entom. Mo. Mag., vol. iii. p. 238) remarks as follows:—'It is pretty well known that in the natural sequence illustraria reproduces itself in the form of delunaria and vice versâ. But what I assert is, that whenever (whether at large, owing to exceptionally hot or long summer seasons, or in captivity from warmth, assisted perhaps by what Mr. Crewe has happily termed "feeding up quickly") the completion of the pupal stage is accelerated, then delunaria produces delunaria, not illustraria. Further, it is my belief