290 LAMELLICORNIA. 



Chrysina, differs from the group to which Chrysina belongs by the distinct frontal suture. 

 This suture is flexuous ; the clypeus is semiovate (in the female more quadrate), with the 

 margins much reflexed ; the mandibles with entire (rounded) outer edge ; and the thorax, 

 margins, and the under surface of the body villose. In short it has all the characters 

 of the Areodinae, with the important peculiarity that it has 9-jointed antennae, in 

 which it differs from all other Rutelinae. The males have greatly enlarged hind legs, 

 with broad, interiorly-flattened femora and tibiae, the inner apex of the latter prolonged 

 and acute, and the trochanters with a long, free, hook-shaped apex. The forehead in 

 the male is flattened, forming a semi-ovate sloping disc. The mesosternum in the male 

 is prominent between the middle coxae, and conical but scarcely projecting ; in the 

 female depressed. In the female the forehead is simple, and the hind legs normal, 

 except that the apex of the trochanters is free for a short space and the inner apex of 

 the tibiae is slightly produced. In both sexes the tarsal claws are very long and acute, 

 and all are simple; they are very unequal in length, and the tarsal joints are short and 

 compact as in all true Rutelidae, so that there is no ground for referring the genus to 

 the Melolonthidae as has been suggested. In the Salle collection the species bears the 

 name of Plectris truquii. 



1. Parachrysina truquii. (Tab. XVI. figg. 23, s ; 24, $ .) 



Chrysina (?) truquii, Thomson, Archiv. Ent. i. p. 148, t. 10. fig. 4 l . 

 Hah. Mexico (Truqui 1 ), Morelia (Salle), Yautepec (Edge). 



The male is more ovate than the female, and differs from it in colour and punctuation, 

 the thorax and elytra being fulvous, the former finely punctured and with an aeneous 

 and smooth dorsal vitta ; in the female the thorax is strongly punctured and brassy- 

 green, with the side-margins broadly fulvous. The size varies from 11 to 15 millim. 



BYRSOPOLIS. 



Byrsopolis, Burmeister, Handb. der Ent. iv. 1, p. 425 (1844). 



A genus hitherto known only from tropical South America, whence four species 

 have been described. They seem to be perfectly congeneric with Burmeister's 

 typical species (known to me only by the description), with which they agree in the form 

 of the maxillae, and especially in the slender tarsi and tarsal claws ; the peculiar 

 form of the labrum is not mentioned by Burmeister — in our species its upper surface 

 is entirely concealed under the clypeus. They approach the Cyclocephalinae, especially 

 the genus Democrates, from which the shorter and closer-jointed hind tarsi chiefly 

 distinguish them and justify their retention in the Rutelidae. This at least applies 

 to the first species, in our two examples of the second the tarsi are wanting. The pro- 

 sternum has a broad, scarcely ascendent, postcoxal process ; the mesosternum is simple. 



