372 TERTIARY INSECTS OF NORTH AMERICA. 



LITHADOTHRIPS Scudder (\tdd?, Opi^}. 



ii-ijix .Sc.iulil., Bull. U. S. Geol. Geogr. Surv. Terr., I, 221 (1875). 



Allied to Melanothrips Haliday. The head is large, broad, globose ; 

 the eyes exceedingly large, globose, each occupying on a superior view 

 fully one-third of the head ; the antennae very slender, equal, as long as the 

 thorax, the joints eight or nine in number, cylindrical, equal, scarcely en- 

 larging toward their tips. The prothorax is no larger than the head, of 

 equal breadth with it, the whole thorax shaped as in Palaeothrips. Only 

 fragments of the wings remain, sufficient to render it probable that they 

 agree well with the character of the group to which Melanothrips and ^-Eolo- 

 thrips belong. The legs resemble those of Palseothrips, but are slender and 

 appear to be rather profusely supplied with hairs. The abdomen differs 

 considerably in the two specimens referred to this genus. In one it is 

 very broadly fusiform, the tip a little produced, nine joints visible, the 

 apical furnished with a few hairs, and bluntly rounded at the tip ; the other 

 has the sides equal, the apex not at all produced, but very broadly rounded, 

 only seven or eight joints vaguely definable. 



A single species is known. 



LITHADOTHRIPS VETUSTA. 



PI. 5, Figs. 88, 89, 102, 103. 



Litliadothrips vetusta Scudd., Bull. U. S. Geol. Geogr. Surv. Terr., I, 222 (1875). 



The specimens, both of which represent the upper surface of the body 

 with fragments and vague impressions of the members, are too poorly pre- 

 served to add anything to the above description of their generic features 

 excepting the following measurements : 



l-'irst specimen : Length of body, 1.76 mm ; of antenna?, 0.6 mm ; of thorax, 

 O.Gt mi "; of abdomen, 0.87"""; breadth of head, ().28 mm ; of thorax, 0.52""" ; 

 of abdomen, 0.5(i mm : length of fore femora, 0.37 mm ?; breadth of same, 

 0.14"""; length of hind femora, 0.42 mm ; breadth of same, 0.13 mm . 



Second *i>rriitin/ .- Length of body, 1.96""" ; of antennae, 0.76 mm ; of 

 thorax, O.. r )(i""" ; of abdomen, 1.10"""; breadth of head, 0.3>( mm ; of thorax, 

 0.59"""; of abdomen, <>.:>!>""". 



Fossil Canon, White River, Utah. Two specimens, W. Deuton. 



