( «x ) 



than those with a tooth only. A large number of Coleoptera 

 of the families Melolonthidse and Rutelidse. have this form. 

 The Rutelidse. differ from the Melolonthidae, in having the two 

 claws of unequal size, the outer one being the larger. Some- 

 times both these claws are simple, but in many cases the 

 larger claw of the anterior tarsi is bifid. In some species the 

 larger claw of all the tarsi, and in some both claws of all 

 the tarsi are bifid. The bifid claw occurs in the Melolojithidse. 

 in such genera as Diphucephala, Macrodactyhc/t, Chaujiantluis, 

 Chasmatopterus, and many others, but both claws are of the 

 same size. 



Many other Coleoptera have bifid claws. Dragon-flies of 

 the genus Macrotnia and its allies and, I believe, all the 

 Agrionidse have this form of claw, although it is often very 

 slight. It is very slight in Ma7itis}oa. All the Fieridaz have 

 the claws bifid, and so have the Tenthredinidee. Among the 

 wasps the genera Rhynchium, OdyneriLS, Eumenes and Synagris 

 may be mentioned. In all these the two points are one below 

 the other, or nearly so. In some species of wasps of the 

 genus Salius, S. basalts for example, the lower point is inside 

 the upper one, and this is so in most of the bees that have 

 bifid claws, such as Bombus, Apathits, Antliophora and 

 Anthidium. In the Longicorn genus Amphionycha nearly 

 the same form occurs, but here the claws are more 

 cvirved. 



Having briefly mentioned the different forms of claw, let 

 us now inquire whether any particular form is associated 

 with any special habit of the insect. Is this difference in 

 the claws merely the result of heredity without any special 

 object, or is there any evidence to show that a special form of 

 claw is adapted to some particular mode of lifej that is to 

 say, has it been developed to meet some particular need? 



In the Coleopterous genus Uroplata the elytra are furnished 

 at the apex with spines and teeth of various shapes, and in 

 no two species are they exactly alike. Broadly speaking, 

 these spines may be of service to the insect, but it is hardly 

 probable that each particular modification is specially advan- 

 tageous to the species which has it. I suggest as a subject 

 for inquiry. Are the claws of insects in the same category? 



