248 



D. T. MacDougal — The Salton Sea. 



the dead stems of some species remaining erect in place held 

 aloft fruits which were not all cast off until after the waters 

 had receded. 



The fact that 4 out of a total of 60 species which found place 

 on the strands exhibited modifications of structures not observed 

 elsewhere led directly to a consideration of the endemic species 

 of the Sink. Atriplex saltonensis Parish, Sphwralcea orcutii 

 Yasey and Eose, Cryptanthe costata Brandegee, Calandrinia 

 ainbigua Howell, Astragalus aridus A. Gray, and Chamcesyce 

 saltonensis Millspaugh are to be included in this category. It 

 is true that Calandrinia is found a short distance beyond the 

 limits of the Sink, but the remaining 6 species are not known 



Fig. 5. 



Fig. 5. Big island, a hill surrounded by the waters of the lake in 1905. 

 Several well-marked strands of Blake sea are visible. 



to occur beyond and above the high beach line which marks the 

 level of Blake sea, which filled the basin to this shore line 

 within comparatively recent time. The situation suggests 

 that these species originated in the Sink since it was 

 last filled and the inference is strongly in favor of such 

 a conclusion. If the possibility of the origination of these 

 forms within the Sink be allowed, it is also suggested that 

 other species might have originated in like manner but become 

 disseminated over a wide area in such manner that their 

 nativity is undiscoverable. 



It became obvious during the course of the work that the 

 origination of qualities or structures upon which dissemination 

 would depend might, in many instances at least, have no possi- 

 ble connection in a causal way with the agencies themselves. 

 Thus for example, the desert gourd which was carried about 



