INVERTEBRATA, CRYPTOGAMIA, MICROSCOPY, ETC. 935 



Another experiment was made with nine females, which were 

 taken three kilometres from the nests, and after being kcjit in confine- 

 ment all night were released, not in the fields, which may jiossibly 

 have been more or less known to them, but in the public street of a 

 town, in the centre of a ])opulous quarter, to which the Cercerides, 

 with their rustic habits, had certainly never penetrated. Each released 

 Cerccris rose up vertically between the two rows of houses, as if to 

 disengage itself as quickly as possible from the street ; then, clearing 

 the roofs, it launched out immediately, with a hasty flight, towards 

 the south, where the nests were. The next day five of the insects 

 were found at the nests (none being visible the previous day). 



Transported to enormous distances, the pigeon promi)tly returns. 

 If we compare the length of the jiassage and the bulk of the creature, 

 the Cerceris, transported to a distance of three kilometres and return- 

 ing to its nest, is much superior to the j^igeon. The bulk of the 

 insect is not a cubic centimetre, and that of the pigion amounts to 

 quite a cubic decimetre. The bird, a thousand times larger than the 

 liymenopteron, should, in order to rival it, regain its home from a 

 distance of 3000 kilometres, three times the length of Franco from 

 north to south. But power of wing, and still less clearness of instinct, 

 are not qualities to be measured by the metre. The relations of bulk 

 cannot here be taken into consideration, and we can only see in tlie 

 insect a worthy rival of the bird without deciding which has the 

 advantage. 



When the jugeon and the Cerceris are artificially removed from 

 home by man and transported to gi-eat distances into regions hitherto 

 uuvisited by them, are they guided by remembrance ? Can memory 

 serve them for a compass when, arrived at a certain elevation, they 

 recover the lost j)oint, and start, with all their power of flight, to that 

 side t)f the horizon where their nests are to be found ? Is it memory 

 wliich traces their route in the air, to traverse regions they see for the 

 first time ? Evidently not ; there can be no remembrance of the 

 unknown. The hymenoptcron and the bird do not know the place in 

 wliich they find themselves ; nothing can have informed them of the 

 general direction in which their displacement may have been eftectcd, 

 for it was in the darkness of a close basket, or of a box, that the 

 journey was made. Locality, orientation, arc unknown to them ; 

 nevertheless they return. 



They have, then, for a guide, something more than simitle remem- 

 brance ; they have a special faculty, a kind of topogra[)hical sense, 

 of which it is impossible for us to have any idea, not having anything 

 analogous to it. 



Nervous System of Oryctes nasicornis.* — Dr. Michelis devotes 

 70 pages and 4 plates to an account of the nervous system of this 

 Lamellicoru Coleojjteron, in its larval, pupal, and adult stages ; 

 like numerous of its allies, it is interesting from the fact that 

 there is a great want of similarity between what is seen in the 

 larval and in the adult form; in the former it is short and com- 



* 'Z.ilM-lir. wirs. Z.M.I.,' xxxiv. (ISSO) p. Gll-702. 



