200 



IIARDWICKE'S SCIENCE-GOSSIP. 



[Sept. 1, 1S6S. 



represented by a poison-tube between the other 

 two. The sting is unbarbed, and in shape like the 

 blade of a narrow, straight-pointed penknife, one 

 exquisitely keen edge of which projects on the out- 

 side of each tube, cut away for that purpose ; the 

 point can also no doubt be thrust beyond the end. 

 It is made up of two very thin plates of a horny 

 substance, united at their edges, the delicate su- 

 ture so formed on the outer or cutting side serving 

 to strengthen the edge, while that at the back, 

 which is thicker, fits into a groove made for it in 

 the strong keeled bar below, in which it has a slid- 

 ing motion. This bar again fits into a corresponding 

 groove in the tube itself, in which it is moved back- 

 wards and forwards by the powerful muscles lining 

 the upper part of the tube. These stings seem 

 fitted rather for cutting and wounding than for 

 killing, and, having no barbs, can be used without 

 danger to the insect itself. The poison-tube, which 

 has a separate sheath, is fixed as stated, between 

 the sting-tubes. It has been removed in the illus- 

 tration from its true place, where it would scarcely 

 be visible. The poison-bag is similar in form to 

 that of the common wasp, and is provided with two 

 sets of muscular bands for contracting it rapidly — 

 one around the smaller circumference, as drawn 

 in the figure, the other underneath and across 

 these. 



When confined in the live-box, the wasp darts 

 out its stings with great vivacity, first on one side, 

 then on the other, together with the poison-tube, 

 which gives out a fluid poison in visible quantity. 

 The abdomen at the same time is much prolonged, 

 and is capabIe,Jno doubt, of bending well under the 



Fig. 21S. Claw of Sand Wasp, x 5f>. 



body between the claws. These, as in ninny, if not 

 all wasps, are prehensile, furnished with two claws 

 for digging; each is hollowed out behind, and a 

 smaller tooth fitted into the cavity, which can be 

 closed or extended, making a pair of pincers. 

 Thus there are twelve pairs of pincers to hold the 

 prey whilst under the command of the formidable 

 stings and poison-tube. The foremost leg is fur- 

 nished with a pecten to brush the antenna:, indicat- 

 ing a habit of burrowing in the ground or in rotten 

 wood. 



Without knowing more than can be gathered 

 from its equipments, it may be surmised that this 

 insect is one, among many species, of those preda 

 ceous little tyrants called Sand or Wood Wasps 

 which carry off unhappy caterpillars and insects, and 

 shut them up with their eggs, in a crippled and 

 stupefied state, as a provision for their future grubs. 

 A summary account of them is given in Wood's 

 "Natural History." No mention is made of the 

 peculiar form of sting now brought under notice. 

 It would probably, however, be found, on a wider 

 investigation, that this is by no means a solitary 

 instance, and that in many cases the sting is simi- 

 larly modified to suit the habits of these very curious 

 wasps. S. S. 



THE GREEN TREE FROG. 

 (Rana arboreal) 



N the December number of the first volume of 

 Science - Gossip, G. Guyon remarks that, 

 although he had often seen toads and natterjacks 

 strike at each other, and at inanimate objects, he 

 had never seen the green frog commit mistakes of a 

 similar nature. 



Having kept a couple of these pretty reptiles last 

 summer, I have had many opportunities of watching 

 their habits, and have often seen them jump at a 

 piece of stick, a pencil, or my fingers, which habit 

 may be accounted for by their usually being fed in 

 one or the other of these ways. It may therefore 

 be presumed that they would not commit such 

 mistakes in a wild state ; if they do, very dis- 

 agreeable results must often follow. I certainly do 

 agree with your correspondent as to their always 

 being on the look-out for food. I think that, com- 

 paratively, they eat more than most reptiles. Mine 

 would at one meal eat, and apparently think nothing 

 of, two or three large blowflies, half a dozen house- 

 flies, a few winged ants, and a drone or two. They 

 can, however, like most reptiles, exist a long time 

 without food. 



When the green frog gets a morsel that is diffi- 

 cult to manage— for instance, a large garden spider, 

 of which mine were remarkably fond — it makes use 

 of its fore-paws, pushing the insect to the front of 

 its mouth, where it can be more easily dealt with. 

 Its food consists of all kinds of spiders, flies, 

 white slugs, small earthworms, and on one occasion 

 mine eat a few pieces of raw lights. Whilst feeding, 

 two of my frogs often, sprang at the same object, 

 the successful one getting, as "C. A." remarks, "a 

 smartish smack on the side of the head" from the 

 tongue of the unsuccessful one — of course not in- 

 tended for the frog, but for the insect. 



The agility of the green frog is surprising, par- 

 ticularly when hungry ; it will leap two or three 



