119 



The general appearance of the plant is suggestive of Euphorbia 

 (in the old sense), but the calyces are much more like those of 

 Croton or Crotonopsis. The species of Croton differ materially in 

 the arrangement of the flowers, but among the scanty materials 

 at my command I have not found one agreeing with the fossil. 

 Possibly C. monanthogynus Michx. is as near to it as anything. 



Hab. — Miocene shales of Florissant, Colorado, Station 14 

 (5. A. Rohtver, 1907). 



Tithymalus Willistoni sp. nov. 



Some time ago I was informed by Dr. WiUiston that seeds of 

 a plant almost identical with the well-known " Snow-on-the- 

 Mountain " had been found in the Loup Fork Beds of Kansas, 

 but had not been described. Through the kindness of Mr. H. T. 

 Martin, I have been able to examine some of these, taken from 

 the interior of a skull from the Loup Fork at Long Island, Kan- 

 sas. As preserved they are perfectly white, and as Dr. Williston 

 stated, they almost exactly agree with the seeds of Tithymahis 

 margiiiatus (Pursh) Ckll. The sculpture is practically the same 

 and the only difference I notice is that they are larger and more 

 robust, 4^ to 5 mm. long, and the larger ones 5 mm. in trans- 

 verse diameter. The suture on one side is very evident. On 

 some of the seeds, the reticulated sculpture has become almost 

 obsolete, but evidently by wearing, as others show it very 

 strongly. This fossil species may be called Tithymahis Willistoni. 



Fossil Saururaceae? 



The Saururaceae constitute a small family allied to the Piper- 

 aceae, with three genera. Saiirurus has one species in eastern 

 North America and one in Asia. Hoiittuynia is Asiatic and 

 Anemiopsis is represented by a single species living in damp 

 alkaline spots in the western United States. Evidently the 

 group is a waning one, and it might be expected that it would 

 occur more abundantly in the Tertiary strata. It has not been 

 recognized as such in our western Tertiaries, but Piper Heerii 

 Lx., an unfigured species from the Eocene at Golden, Colorado, 

 may belong there. According to Lesquereux, P. Heerii is 

 exceedingly like P. antiquum Heer, a fossil from Sumatra. This 

 P. antiquum, in the shape and venation of the leaf, agrees 

 excellently with Houttuyjtia, and probably belongs to that genus. 



