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Show 630 MR. J. WOOD-MASON ON THE FAMILY EMBIIDJE. [Dec. 18, camping-ground. A violent thunder-storm which suddenly came on while I&was searching for the nest or tunnels inhabited by the insects drove me indoors ; and, having to resume m y journey shortly afterwards, I had much against my will to forego an opportunity of ascertaining the habits of the Embiidse that may not soon recur. Not expecting to meet with Embia in such a place, I should have passed them over without notice had it not been for their marked Thysanu-rous gait and shape ; and I was much disappointed at finding, as I soon did, that instead of a new Thysanuran with two-jointed cerci and a living representative of the ancestors of the Staphylinida?, I had got hold of an Embia. Some of the specimens obtained on this occasion were forwarded to Mr. M'Lachlan l, who has expressed the opinion that they probably belong to Oligotoma saundersii of Westwood, a species originally described from Calcutta specimens. In none of those which were retained by me for m y own use are the slightest traces of wings to be detected, although the asymmetry of the caudal appendages, which I consider to be characteristic of and exclusively confined to the male sex, is already quite apparent. The asymmetry of the tergum of the terminal abdominal somite and of the cerci in the males of Necrosia maculicollis, one of the Phasmatidse, appears at the corresponding early stage, and in nymphs is quite as strongly marked as in perfect insects. Discovery of a Female.-In the following October, on the first zoological excursion I made after my return to Calcutta, I met with an insect possessing all the characters, including the peculiarly fashioned fore legs of the Embiida?, but devoid of all traces of wings and abdominal asymmetry. I found it in the large plant-house in the Botanic Gardens, crawling over the leaves of a plant of the habit of Fittonia. It is a shining black insect with pale-tipped antennae, and as it lay upon the leaves it bore a striking resemblance to a larva of some hrachelytrous beetle or to an Earwig with a short forceps. It measured no less than three quarters of an inch in length from the front of the head to the end of the abdomen, and is consequently about thrice as large as the smallest, and twice as large as the largest, of the previously described specimens, compared with which it is further remarkable for its thick aud firmly chitinizedintegument. It, in fact, answers exactly to the idea I had formed of what the female would be like, and it is, as I shall show, a female. Description of the Female.-In its abdomen, counting the so-called "segment tnediaire" as the first somite, as it unquestionably is, though here, as is often the case in other groups of insects, its tergum is firmly ankylosed to the metathorax in adults and its sternum appears to be undeveloped, ten terga, the full number of the typical insectean abdomen, are externally visible, the two penultimate ones (which in the Cockroach and in the Earwig are shortened and squeezed up out of sight between the last or tenth and the seventh) being equally well developed with the rest; the last or tenth tergum is entire, rounded, obtuse, and deflexed at the end, and, with the two-jointed 1 Proc. Ent. Soc. 1879, p. xliii. |