Horn.] 



OPHRYASTINI. 37 



type and this character appears to be of minor importance in classification 

 in the present tribe, as two other genera already mentioned have the third 

 joint feebly emarginate and not wider than the third. 



Rh. effracta Lee. Amer. Nat., 1874, p. 459. 



Form oval, color piceous densely covered with cupreous scales almost 

 entirely obscured by a dark brown exudation. Head and rostrum as long 

 as the thorax. Rostrum above trisulcate, tip obliquely truncate, front 

 slightly concave and with a hood-like tubercle over each eye. Thorax 

 broader tlian long, sides at anterior third more rapidly narrowing, posterior 

 two-thirds feebly converging to the base, surface tuberculate and very 

 irregular. Elytra oval, disc slightly flattened, humeri slightly oblique and 

 with moderately large tubercle, from which a ridge or costa arises forming 

 the lateral margin ; disc bicostate, the outer terminating in a tubercle at 

 the sides of the declivity, intervals with large fovese separated by smaller 

 ridges uniting the costte ; tip of elytra with smaller tubercle on each side. 

 Body beneath scaly obscured with exudation and with short scale-like 

 liairs. Legs dark brown, sparsely scaly and with fine scale-like hairs. 

 Length .20-.26 ; 5-6.5 mm. 



The appearance of this insect is that of a miniature Bhigus, or of some 

 Leptops. Its afiinities appear to be rather with Ophryastes than with any 

 other genus. 



Occurs in California feeding on the Yucca. 



Group IIL Strangaliodes. 



The group as made up in the following table is not precisely that in- 

 tended by Lacordaire. There are without doubt several genera which 

 should be placed in Iris Eremnides, but with the exception of PliyxeliH I 

 can find no genus presenting such marked differences in the form of the 

 scrobes as to render it possible t'o draw the line with any degree of accuracy 

 between those genera in which the scrobes are strictly lateral and those 

 with the scrobes arcuate and directed inferiorly. , 



The arrangement of the genera in the following table exhibits a gradual 

 transition in the form and length of the rostrum, from Diclwxenus which 

 approaches most nearly Ophryastes in this respect as well as in the struc- 

 ture of the scrobes and abdomen, to Phymatinus with a long rostrum 

 almost entirely lateral scrobes and normal abdomen. Cimboeera by its 

 narrower tarsi and the structure of the antennae approaches OpJiryastes in 

 another direction. Melamomplius resembles almost Y)vec\?,e\j Amomphua 

 in form. 



I have not been able to obtain anj^ characters from the form of the corbels 

 of the hind tibiae, but have been compelled to group seven genera by a 

 character almost as feeble, the presence or absence of mucro at the tip of 

 the hind tibiae. Our genera exhibit sucli a similarity of structure that it 

 is almost impossible to define tlieir limits and with the addition of new 

 material generic definition will be reduced to a work of extreme difliculty. 



