CLARK: RECENT CRINOIDS 



579 



^ 



mixed tyuyamunite and carnotite, then there must be present 

 35 per cent of these two minerals. As, however, special tests 

 showed that both tyuyamunite and carnotite are insoluble in 

 ammonium carbonate solution whereas the material analyzed dis- 

 solves therein with great ease and readiness, the assumption that 

 the lime and potash present are due to these two minerals is 

 disproved. It is not known whether the lime and potash are 

 derived from the gangue or belong to the uvanite. The ratios 

 deduced on the basis of either assumption are the same. 



Ratios of uvanite analysis 



NEGLECTING CaO + K2O 



UO3 0.139 or 1.91 or 2X0.96 



V2O5 0.208 or 2.86 or 3X0.95 



H2O 1.106 or 15.22 or 15 X 1.01 



COMBINING CaO + K4O WITH UOl 



UO3 0.150 or 2.05 or 2X1.03 



V2O5 0.208 or 2.84 or 3X0.95 



H2O 1.106 or 15.11 or 15 X 1.01 



The formula derived for uvanite is 2UO3.3V2O5.I5H2O. 



Analysis of another mineral from the south side of Temple 

 Rock, Emery County, Utah, which occurs in shaley sand- 

 stone as small greenish-yellow, glistening scales, has shown it to 

 be like uvanite, a hydrous uranium vanadate. Further investi- 

 gation is being made to determine whether it is a new species or 

 a variety of uvanite. 



Pascoite- has been found in small quantity on the Crescent 

 No. 3 claim. Crescent Creek, Henry Mountains, and at a num- 

 ber of other places in southeastern Utah, as an efflorescence 

 (already mentioned) and in cavities in fossil wood. 



ZOOLOGY. — The relation between recent crinoids and the tempera- 

 ture of their habitat. Austin H. Clark, National Museum. 



I have already discussed at considerable length^ the relation 

 between the recent crinoids and the temperature of the water in 



1 Une etude philosophique de la relation entre les crinoides actuels ot la 

 temperature de leur habitat. Bulletin Xo. 294 de I'lnstitut Oc^anographique. 

 Monaco, 1914. 



2 Hillebrand, W. F., Merwin, H. E., and Wright, t. E. Hewettite, metahew- 

 ettite and pascoite, hydrous calcium vanadates. Proc. Am. Philos. Soc, 53: 31- 

 54. 1914. 



