218 SUMMARY OF CUBEENT RESEABOHES RELATING TO 



more perfectly developed Culicidse and Tipulidse, show considerable 

 affinities to the larvae of Lepidoptera. 



The embryo bee has a pair of temporary appendages on each 

 segment, as also have the embryos of Coleoptera and Lepidoptera, vrhich 

 points to an early Scolopendra-like ancestor, which in its turn indi- 

 cates a still earlier Peripatus-lihe ancestor from which the Myriopoda 

 and Insecta, at least, if not the Arachnida, have been derived. 



Development of Antennae in Insects.* — J. Dewitz does not agree 

 with the account of the development of the antennae of insects given 

 by Graber, who thinks that the point of insertion of the antennae 

 moves from the ventral to the dorsal aspect of the head. Dewitz finds 

 that if we make a longitudinal section through the head of a half- 

 grown caterpillar, we find an elongated saccular structure at the base 

 of each tentacle ; these, which lie below the sutures of the clypeus, are 

 the rudiments of the antennas of the butterfly. The sac in question 

 is formed by the invagination of the matrix at the base of the cater- 

 pillar's tentacle into the interior of the head ; the sac is double-walled, 

 and in young caterpillars the two walls are of the same thickness and 

 lie close to one another. Later on, the outer becomes thin and trans- 

 parent, while the inner becomes folded, as it grows. The orifice of 

 the invaginated sac is at first wide, but later on becomes narrower. 

 Tracheal and other tissues grow into the cavity of the sac, and it is 

 at their expense that the antenna is formed. Between the two walls 

 there is a layer of chitin, which, though very delicate, consists of two 

 lamellae. The author has not yet been able to determine exactly how 

 the antennae become free. 



Experiments with the Antennae of Insects.f — C. J. A. Porter 

 details some experiments which he has made on the antennae of insects 

 with the view, if possible, of determining their function, and as the 

 result of these experiments he has been led to the following con- 

 clusions : — 



1st. The antennae are not the organs of any one of the so-called 

 five senses, or of any combination of them. It is true that insects 

 often seem to be able to tell the difference between good and bad 

 tasting things brought into contact with the antennae, but the 

 author does " not think we have any reason for saying that insects 

 taste with their antennae, because they dislike to have such things as 

 pepper-sauce poured on them, than we would have for concluding that 

 a man tastes with his nostrils simply because he would object to 

 having them filled with the same fluid. But on the other hand, this 

 apparent sense of taste is, in many instances, nothing more than the 

 insect's desire to clean off whatever may be put on its antennae." They 

 are mostly kept very clean by the insect, and are, as a rule, of all parts 

 of the body most free from extraneous matter. They seldom notice any- 

 thing put to them unless it be of a nature to adhere to them. But 

 as soon as anything, even pure water, sticks to them, they immediately 

 draw them through the mouth-parts, and if it be anything palatable, 



* Biol. Centralbl., iii. (1883) pp. 582-3. 

 t Amer. Natural., xvii. (1883) pp. 1238-45. 



