2/6 COLEOPTERA 



CHAP. 



Series V. Phytophaga. 



Tarsi apparently four-jointed, the three basal joints usually densely 

 set with cushion -like pubescence beneath; the third joint 

 different in form, being divided into two lobes, or grooved 

 on its upper surface so as to allow of tit e fourth joint being 

 inserted near its base instead of at its extremity. Head not 

 forming a definite prolonged beak ; its labrum visible, the 

 palpi rarely (and even then not con^letcly} occluded in the 

 mouth. 



This great series of beetles includes something like 35,000 

 species. It approaches, like all the other series, the Polymorpha, 

 especially the family Erotylidae placed therein, Imt in the great 

 majority of cases there is no difficulty in recognising its 

 members. The tarsi have never the Heteromerous formula, the 

 head is not constructed like that of Ehyuchophora, nor the 

 mouth and feet like those of Adephaga ; the antennae are 

 different from those of the Lamellicorns. The tarsi are really 

 five-jointed, for careful inspection shows that the long claw-joint 

 has at its extreme base a small nodule, which is undoubtedly 

 the fourth joint (Fig. 142, B). In speaking of the joints it is, 

 however, customary not to refer to this small and functionally 

 useless joint at all, and to call the claw-joint the fourth ; when 

 the little joint is referred to it may be called the true fourth 

 joint, 



Nearly the whole of the enormous number of species of this 

 series are directly dependent on the vegetable kingdom for 

 their nutriment ; they are therefore well styled Phytophaga. 

 This term is, however, restricted by some systematists to the 

 family we have called Chrysomelidae. Although there is 

 enormous variety in this series, three families only can be at all 

 naturally distinguished, and this with difficulty. Of these the 

 Bruchidae are seed -feeders, the Chrysomelidae, as a rule, leaf- 

 feeders, the Cerambycidae wood and stem-feeders. The number of 

 exceptions to this rule is but small, though certain Cerambycidae 

 and certain Chrysomelidae live on roots. 



Fam. 77. Bruchidae. Prosternum extremely short ; in front 

 perpendicular; behind the coxae, forming merely a transverse 

 lamina with pointed extremity. Hind femora more or less 



