38 bulletin: museum of comparative zoology. 



It thus appears that so far as the venation shows, the Florissant species are 

 nearest to some of those flying in Colorado at the present day. In the follow- 

 ing descriptions, those characters are italicized which may especially be relied 

 upon for the separation of the fossil species. 



Anthidium scudderi, sp. nov. 



Robust, probably about 15 mm. long (the end of the abdomen is lacking) ; 

 width of thorax about 5 mm. (probably increased by flattening), of head about 4£ ; 

 general appearance normal ; head and thorax black, with faintly indicated light 

 markings ; apparently the clypeus was light, and a large patch on vertex, and a 

 pair of longitudinal subdorsal stripes on anterior part of thorax (mesothorax), but 

 these markings, vaguely indicated by reddish color, may not truly represent the 

 tegumentary colors ; mandibles apparently short and heavy ; antennae and legs not 

 visible; abdomen broad, very pale reddish, with the hind margins of the segments 

 infuscated, the darkening strongest on the actual margin, and gradually fading 

 anteriorly, the dark band occupying about a third of the visible part of the segment 

 (much less on the first) ; on the second to fourth segments are rather poorly indi- 

 cated dark marks in the subbasal region in the middle line, and on each extreme 

 lateral margin, apparently indicating a subbasal band very broadly interrupted in 

 the subdorsal region ; it is perhaps probable that the abdomen was in life yellow 

 marked with ferruginous ; the apparent pattern is not quite like that of any 

 modern species before me, but it is not difficult to see how it might become modified 

 into some of the patterns seen in modern Rocky Mountain species. Quite a close 

 general resemblance is shown by the abdominal pattern of A. bernardinum, but in 

 that species the lateral subbasal dark spots are much nearer the middle line. 



Anterior wings about 8 mm. long ; wings strongly infuscated, except in the basal 

 region, conspicuously hairy. Venation in general quite normal ; marginal cell broad, 

 its width about 720 /j. ; b. n. going only just basad of t. n. ; first r. n. joining 

 second s. m. a long distance (quite 420 ft) from base ; discoidal nervure oblique 

 and curved, so that the second discoidal cell is conspicuously longer on lower than on 

 upper side, the upper outer corner being very obtusely rounded. Hind wing with 

 t. m. longp and very oblique. 



Type. — No. 2002, Mus. Comp. Zool. Florissant, Col. (No. 11,381, S. H. 

 Scudder Coll.). Dedicated to Mr. Scudder. 



Anthidium exhumatum, sp. nov. 



<f Robust ; length 13| mm. ; width of head a little over 4, of thorax about 5, of 

 abdomen about 5£ mm., these measurements (particularly the last) no doubt 

 increased by crushing ; head and thorax black without any apparent markings ; 

 mesothorax coarsely roughened ; ocelli large, not approaching eyes, distance be- 

 tween middle and lateral ocelli a little less than the diameter of one ; abdomen 

 with broad pale reddish bands, the hind margins of the segments not darkened, nor any 

 spots visible ; apex broadly rounded, no processes or teeth being visible, but a large 

 quadrate area is occupied by the genitalia, the exact structure of which cannot be 

 made out ; hind tarsi apparently broad and flattened ; hind tibiae with a rather 

 abundant hairy scopa. Wings colorless ; nervures pale; marginal cell not so broad 





