of the Coleopterous Genus Gyriosomus. 259 



slender ; it differs moreover, constantly, in having the sutm-e of 

 the elytra raised into a keel. The white markings on the elytra 

 resemble those of G. Hopei, and are slightly impressed in the 

 same way. 



Gyriosomus marmoratus. Gyr. ovatus, nitidus ; elytris maculis valde 

 irregularibus albis impressis. Long. 9;!^ — lOlin. ; lat. 5| — 5|lin. 

 Found on the mountains near Villa Vicuiia, province of Coquimbo. 



Tliis species is intermediate in form (and in its characters ge- 

 nerally) to the Gi/)-iosomiis Hopei and the G. lavigatus. The body 

 is convex, ovate, and very glossy. The head has a few distinct 

 scattered punctm-es in front, and a transverse depression in a line 

 with the points of insertion of the antenna. The thorax is trans- 

 verse, very convex, broader behind than in front, and has the sides 

 slightly rounded. The elytra are smooth and glossy, but wth 

 irregular depressions in parts ; and these depressions are filled 

 with scales or powder-like substance producing most irregular 

 markings and varying much in individuals ; there are generally, 

 however, three or four largeish irregular white patches towards the 

 sides (or rather the lateral keel) of the elytra ; a few small spots 

 on the disc : sometimes there are a series of small spots arranged 

 in a line near the suture, and often the lateral larger patches have 

 a tendency to run into each other by throwing out an oblong 

 mark near to and parallel with the lateral keel ; this is prominent 

 and distinct, and almost reaches the apex of the elytra; it is rough, 

 and divided by a longitudinal groove. 



Gyriosomus elongatus. Gyr. elongatus, subovatus (lateribus corporis 

 in maribus fere parallelibus), ater, squamulis piliforraibus fusco- 

 albis plerumque vestitus. Capite indistincte punctulato ; thorace 

 transverso, lateribus ante medium dilatato, disco convexo, rugoso ; 

 elytris squamulis albo-fuscescentibus dense tectis, at lineis pluri- 

 bus subelevatis, obliquis, vel longitudinalibus, denudatis notatis. 

 Long. 11 lin. 

 This species is found in the plains between Huasco and Coquimbo. 



The legs and antennse in this species are rather longer and 

 stouter than usual in the genus ; these are for the most part co- 

 vered, as well as the body, with very minute, adpressed, brownish- 

 white hairs. The insect appears, in fact, as if it had been pow- 

 dered with dust, but on the elytra the powder-like substance is 

 much more dense than in other parts ; it is however broken up by 

 denuded portions which are slightly raised and form lines which 

 vary in individuals, but the common type of the black markings 

 is as follows : on the basal third of each elytron is a central lon- 

 gitudinal broadish black mark, throwing out in an oblique direc- 

 tion one or two narrower lines ; on the remaining two-thirds of 



