of the Amazon Valley. 101 



1. Lagocheirus araneiformis, Linnaeus. 



Cerambyx araneiformis, Linn. Syst. Nat. ii. p. 625; Drury, Illustr. ii. 



t. 36. f. 4. 

 Acanthoderes araneiformis, Serv. Ann. Soc. Ent. Fr. iv. p. 30. 



L. oblongus, postice modice attenuatus : thoracis tuberculis laterali- 

 bus acutis : elytris nigro fasciculatis, olivaceo-griseis, macula 

 magna laterali triangulari fusco-nigra lineisque transversis pallidis 

 ornatis : tarsis articulis duobus basalibus griseis, duobus apicalibus 

 nigris nitidis. Long. 7—11 lin. S $ . 



This is a well-known and widely distributed insect. I found 

 it occasionally at most stations on the banks of the Amazons, 

 from Para to Peru : it is also a native of Guiana, the West Indian 

 Islands, and the Island of Tahiti, where, according to M.Vesco*, 

 it is common, the larva inhabiting the trunks of Spondias dulcis. 

 It is not stated whether the Tahitian examples differ from those 

 of America ; those of the West Indian Islands form a tolerably 

 distinct local variety. The species, however, has probably been 

 introduced by the agency of man into the distant Polynesian 

 island. 



2. Lagocheirus fasciculatus, White. 



Trypanidius fasciculatus. White, Cat. Long. Col. Brit. Mus. ii. p. 377j 

 pi. 9. f. 9. 



L. oblongus, postice valde attenuatus : thoracis tuberculis lateralibus 

 obtusis : elytris nigro fasciculatis, olivaceo-griseis, maculis duabus 

 lateralibus triangularibus (altera magna, altera parva) fasciaque 

 lata pallida ornatis : tarsis ochraceis, articulo ultimo apice nigro. 

 Long. 8-9i lin. S $ • 



Not uncommon at Ega, Upper Amazons, on dead branches in 

 the forest, in company with Acrocinus trochlearis and other wood- 

 eating Coleoptera. The tubercle at the tip of the sixth anten- 

 na! joint of the males is much larger in this species than in L. 

 araneiformis. The figure given in White's Catalogue represents 

 a female. 



Genus Leptostylus. 



Leconte, Journ. Acad. Nat. Sc. Philad. n. s. ii. p. 168. 



Syn. Amniscus, Dej. Cat. (part.). 



The chief characters given by Leconte as distinguishing this 



from the allied genera are the shortness of the basal joint of the 



posterior tarsi and the tuberculose surface of the thorax, whose 



sides are simply prominent instead of being armed with a tooth 



or spine. The genus consists of a number of small-sized species 



more nearly allied to Lagocheirus than to Leiopus and Acantho- 



cinusy being of compact, oval, convex form, and having short 



* Leon Fairmaire, Coleopteres tie la Polvnesie, p. 88. 



