FOSSIL COLEOPTEEA 



17 



indistinct eostee, between which the surface is roughened. Legs and antennae 

 lacking. Length, 2.75 mm. 



Resembles in size and general appearance the insect described 

 by Scudder under the name Hylesinus extractus. The present 

 species has a different prothoracic outline and the elytra are 

 relatively shorter in comparison with the length of the pro- 

 notum. It is much smaller than Xylohiops lacustre from the 

 Florissant shales. The genus Dinoderiis is widely distributed, 

 and is well represented in North America. The insect in hand 

 would go near to the recent D. punctatus by its sculpture, but it 

 is differently proportioned. 



Aphodius III. 



A. PR.EEMPTOR n. sp. (Plate VI, Figs. 1. 2.) Form moderately elongate, 

 subparallel. Head incomplete, the anterior margin being injured on that 

 slab which shows the dorsal view, but judging from the ventral aspect the 

 sides of the clypeus are nearly straight and convergent to the apex which is 

 truncate and without teeth or prominent angles. Prothorax with moderately 

 arcuate sides, disk scarcely punctured, a few shallow punctures laterally. 

 Scutellum short. Elytra injured at base but apparently about as wide as 

 the prothorax. finely striate, the striae not very deep and only finely punc- 

 tate, the punctures longitudinal. Legs stout, tibiae too much injured to 

 show the teeth distinctly. Mesosternum not carinate. Length, 5.65 mm. 



Easily distinguished from any of the other Florissant species 

 of Aphodius of similar size by the type of elytral striation and 

 punctuation. It would come near the fossil A. aboriginalis. The 

 subjoined table will serve as a guide to the identification of the 

 species thus far known from these shales. 



Size very small (under 3.00 mm.). Form stout, elytral striae deep, fine, 

 and apparently impunetate; (2.95 mm.). sJioshonis. 



Size greater (3.50 mm. or more). 

 Size moderate (3.50 to 6.50 mm.). 



Elytral striae duplicate, impunctured; (5.25 mm.). fforissantensis. 

 Elytral striae simple, punctate or not. 



Much smaller (3.50 mm.) ; stria? impunetate. restntctus. 



Larger (over 5.00 mm.) ; striae punctate. 



Thoracic disk distinctly punctate. Elytral striae sharp, well im- 

 pressed, with rounded punctures; (6.25 mm.). granarioides. 

 Thoracic disk nearly impunetate. Elytral striae wide, fairly 

 distinctly punctate; (6.50 mm.). aboriginalis. 



Thoracic disk with rather indistinct scattered punctures. Elytral 

 striae sharp, narrow, with fine elongate punctures; (5.65 mm.). 



praeemptor. 



Size very large. Elytral strife fine, not closely punctured; (9.25 to 



10.00 mm.). laminicola. 



< VI— 4— 2 



