462 COLYDIIDA. 
ILLESTUS. 
Iilestus, Pascoe, Journ. Ent. i. p. 33 (1863). 
This genus was established for a single species, but according to Horn (Proc. Am. 
Phil. Soc. xvii. p. 570) it is probably not sufficiently distinct from the North-American 
Lasconotus, Er. 
1. Illestus terrenus. 
Illestus terrenus, Pascoe, Journ. Ent. ii. p. 38, t. 3. fig. 4°. 
Hab. Mexico}, Las Vigas, Esperanza, Toluca, Jalapa (Hoge), Volcan de Orizaba 
(Sallé). 
Var. tristis. 
Bitoma tristis, Sturm, in litt. 
Hab. Mexico, Salazar, Toluca, Huitzo, Cordova (Hége) ; GuaTEMaLa, Totonicapam 
8500 to 10,500 feet, Quiche Mountains 7000 to 9000 feet (Champion). 
This is apparently a common and variable insect. In most of the examples the 
thorax is nearly straight at the sides, instead of being deeply constricted in the middle ; 
these specimens are usually smaller in size than the examples with constricted thorax, 
and at first appear to be specifically different, but in the series before me there are 
some intermediate examples. 
XUTHIA. 
Xuthia, Pascoe, Journ. Ent. ii. p. 128 (1863). 
? Eulachus, Erichson, Naturg. Ins. Deutschl. iii. p. 275, nota (1845). 
I have not seen the Antillean insect for which the name of Hulachus was proposed, 
and cannot therefore say whether it be really congeneric with Xuthia, Pascoe. This 
point can only be decided by an examination of Erichson’s type. 
I do not think it would be at present advantageous to unite Xuthia with Bitoma. 
Although the characters hitherto made use of to separate the two are but slight, yet 
there is a well-marked distinction in appearance, so that it is probable that minute 
examination will reveal more important distinctions than those at present known. 
Xuthia has been hitherto only known from Celebes, Morty I., and other eastern 
localities, but it was met with by Mr. J. J. Walker in the Marquesas Islands, so that 
its occurrence in the New World is not surprising, even in the event of Hulachus. 
proving distinct. 
1. Xuthia brevipes, sp. n. (Tab. XIV. fig. 22.) 
Sat elongata, ferruginea, subcylindrica, opaca ; prothorace fortius, elytris subtilius, costatis. 
Long. 22? millim. 
Hab. MExico, Cordova (Sallé); Panama, Volcan de Chiriqui (Champion). 
