204 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY 



of the presence in it of several Upper Clarno species. Collections during the 

 past season have increased the number of species known from the flora and 

 have shown a dominance of Miocene species which occur in the Mascall of 

 Oregon. The occurrence of several Eocene species suggests that the Payette 

 is somewhat older than the Mascall. It differs from the latter in having 

 abundant sycamores, poplars, and other lowland types, indicating a habitat 

 somewhat different from that in which the Mascall sediments were laid down. 



FLORA OF THE RANCHO LA BREA 

 BY RALPH W. CHANEY 



(Abstract) 



The abundance of vertebrate remains from the Rancho La Brea deposits of 

 southern California has emphasized the paucity of the fossil plants. The only 

 well defined leaves which have been secured are those of an oak much like the 

 living Qucrcus agrifolia; a few acorns resembling those of the same species 

 have also been obtained. Cones of the knob-cone pine, Finns attenuata, and 

 of the Monterey cypress, Gupressus macrocarpa, are present in small numbers, 

 and there is an abundance of wood which has been referred to Gupressus. 



During the past summer a considerable amount of tar was carefully exam- 

 ined, but, aside from wood, a few undetermined seeds and stems resembling 

 those of aquatic plants were the only materials collected. Further search may 

 uncover situations where plants accumulated in abundance, but, on the basis 

 of the material at hand, it appears that conditions did not favor the accumu- 

 lation of plants. A possible explanation for these unfavorable conditions may 

 be that the level topography did not permit much transportation of leaves and 

 fruits, and that an arid or senna rid climate restricted the number of arbo- 

 rescent types much as it does today. The habitat indications of the known 

 flora are quite consistent with this explanation. 



The next paper, presented by the author and illustrated by many in- 

 structive lantern slides, was of special interest on account of its wide 

 scope and general subject-matter. 



J' I VEX OF THE MESOZOIC AND THEIR RELATIONSHIP TO OLDER AND MORE 



MODERN TYPES 



BY EDWARD C JEFFREY 



(Abstract) 



The author has had the opportunity of studying recently many hundreds of 

 specimens of Cretaceous representatives of pines and allied forms. It t is clear 

 from such studies that there were interesting types present at the epoch 

 transitional between our modern pines and still more ancient types. It is a 

 well established fact that existing pines are characterized by a definite and 

 small number of needles in each cluster or short shoot. In the Cretaceous 

 there were types with many needles on a short shoot. Further in the midst 

 of the needles \v;is a cluster of rudimentary leaves indicating a less degree of 



