104 PROCEEDINGS OF THE NATIONAL AlUSEUM. vol.51. 



Contracted (linear) part of lanceolate cell 960 



End of contracted part of lanceolate cell to lower end of transverso- 

 medial nervure 1, 1-31) 



Miocene shales of Florissant (Geo. W. Wilson). Should this be 

 separated from the original //. eophila, the specimen collected by 

 Wickham at the Wilson Kanch would go with it. 



ERIOCAMPOIDES MICRARCHE, new species (Tenthredinidac). 



Length, 6.5 mm. ; anterior wings, about 5.5 mm. ; mesothorax pale, 

 other parts of thorax darker; abdomen pale, with the apical third 

 fuscous, the extreme base also dusky; antennae with all the joints 

 visible, except the two short (basal) ones, the joints measuring as 

 follows in microns: (3.) 432, (4.) 240, (5.) 240, (6.) 208, (7.) 160, 

 (8.) 160, (9.) 192. The last two antennal joints look, at first sight, 

 like a single one ; the others are more distinct, as usual in the group. 

 The venation agrees well with Eriocampoides, as figured by MacGil- 

 livray.^ The transverse-costal nervure is rather more basad, the 

 third submarginal cell has its side on first marginal longer than on 

 second, and the transverso-medial nervure has its upper end well be- 

 yond the middle of the first discoidal cell (as in Phyllotomu) ; the 

 first discoidal cell is widened basally, its two sides being far from 

 parallel, and the basal nervure is straight, not bent near its lower 

 end. The hind wing is like that of E. aethiops in all essential fea- 

 tures, but the median cell is more produced and very narrow at the 

 apex. 



The following measurements of the anterior wing are in microns: 



Transverse-costal nervure basnd of upper end of basal, about 640 



Narrow upper side of first discoidal cell 208 



Length of basal nervure 750 



Lower end of basal nervure to transverso-metliul 750 



First discoidal on .second submarginal 256 



First discoidal on second discoidal 416 



Lower side of second discoidal 770 



Length of first .submarginal cell 320 



Apical side of second submarginal cell 208 



Third submarginal on first marginal 560 



Third submarginal on second jtnarginal 544 



Third discoidal on second submarginal 640 



Third discoidal on third submarginal 400 



Third discoidal on first discoidal 400 



Thii'd discoidal on second discoidal 480 



Lower side of third discoidal 912 



Apical side of third discoidal 592 



Miocene shales of Florissant (Geo. W. Wilson). 

 II olotype. —C^t. No. 61999, U.S.N.M. 



Very much smaller than E. revelatus Cockerell, already known 

 from Florissant. 



1 Proc. U. S. Nat. Mus., vol. 29, pi. 30, fig. 52. 



