Some Hypermetamorphic Beetles 3 



Pyrochroidae have the hind coxae prominent, the claws simple, 

 and the head horizontal. The antennae are H-jointed, serrate 

 or snhpectinate in the female, and ramose in the male, very 

 nearly filiform. 



The preceding families have normal metamorphosis so far as 

 known, are found on plants, and are not parasitic. The three 

 remaining families have hypermetamorphosis, and although the 

 first two families are found on plants in their adult and beginning 

 stages, they are parasites during the intermediate stages of 

 growth. 



The Meloidae, like the preceding family, have large prominent 

 hind coxae. The claws are cleft or toothed. The vertex is verti- 

 cal. The antennae are,, as a rule, filiform, though sometimes 

 thickened and sometimes reduced. Elytra frequently truncate. 



The Rhipiphoridae have the prothorax at base as wide as the 

 elytra, while in the three preceding families it is narrower. The 

 antennae are n-jointed (10-jointed in certain females); pectinate 

 or flabellate in the males, and frequently serrate in the females. 

 As in Meloidae, the elytra are truncate, sometimes being very 

 small (Myoditcs) and being entirely wanting in Rhipidius female. 

 The claws are seldom simple. 



The Stylopidae have a very much reduced prothorax, aborted 

 elytra, and reduced flabellate antennae in the males and complete 

 degeneration in the females. 



From this brief review we find the place of the three parasitic 

 families lower than the other plant-feeding families. There is of 

 course degeneration in habits. Degeneration of the elytra! and re- 

 duction in the number of antennal joints are the principal external 

 proofs of degeneration. It is interesting to note the increase 

 of flabellation in the antennae as we approach the last family. 



Let us mention here a discrepancy which in our mind should 

 be overruled as being due to degeneracy rather than develop- 

 ment. Stylopidae will not run in tables to Heteromera because 

 of the number of tarsal joints. The fossil genus Triaena Menge 

 had five-jointed tarsi and two claws. Stylops and Xenos have 

 four-jointed tarsi and no claws. Hulictophagits has tarsi three- 

 jointed and Elcnchus two-jointed (apparently). This is as they 

 have been described. 



155 



