AMERICAN COLEOPTERA. 219 



Description of a new species of DACODERUS front the 

 island of Sanfo Domingo. 



BY GEORGE H. HORN, M. D. 



DACODERUS, Lee. 



D. dominicensis, n. sp.— Castaneous, shining. Head with deep frontal 

 impression ; at middle nearly smooth, at sides with coarse elongate punctures; 

 eyes feebly prominent. Thorax longer than wide, sides at anterior third 

 rapidly narrowing, posteriorly very feebly narrowed, at posterior third a sudden 

 and deep constriction, the constriction at sides bridged by an oval tubercle, 

 median line with broad smooth impression, narrower on the posterior third, 

 surface sparsely punctured at the sides. Elytra oblong, base feebly emargin- 

 ate, humeri obtusely prominent, sides feebly arcuate, disc moderately convex, 

 sutural stria feebly impressed, surface with fine punctures sparsely and irregu- 

 larly placed, each bearing a very short hair. Body beneath shining, very 

 sparsely punctate. Length .18 inch; 4.5 mm. 



The specimens before me are all ma es, and have a very small brush 

 of hair on the lower edge of the anterior femora near the middle. In 

 the male of sfriaficeps, there is a m nute spine. 



The differences between the two species are as follows : 

 dominiceusis. 



Head. — Smooth at middle, sides with 



few punctures. 

 Thorax. — Sides with few punctures. 

 Elytra. — Moderately convex, punctures 



fine. 

 Male. — Anterior femur with small 



brush of hair. 



striaticeps. 



Surface deeply striate. 



Surface deeply striate. 



Flat, punctures coarse and elongate. 



Anterior femur with minute tooth. 



The tarsi and antennae are both more slender in the Dominican 

 species, and the underside and legs less coarsely punctured. 



The occurrence of a species of Dacoderus in Santo Domingo, is a 

 curious fact in geographical distribution, and leads us to expect other 

 forms in Mexico. May not this genus be one of the survivals of 

 the period when the islands of the Gulf were continuous with the 

 mainland ? It is certainly one of the isolated forms among the 

 Tenebrionidae. 



For this interesting form, I am indebted to Mr. W M. Gabb, whose 

 labors in developing the geology and geography of Santo Domingo, 

 are widely and favorably known. 



