GEOLOGICAL SUEVEY OF THE TEERITOEIES. . 373 



PRELIMINARY LIST OF THE FOSSILS COLLECTED BY DR. HAY- 

 DEN'S EXPLORING EXPEDITION OF 1871, IN UTAH AND 

 WYOMING TERRITORIES, WITH DESCRIPTIONS OF A FEW 

 NEW SPECIES. 



BY F. B. MEEK. 

 SLLTJEIAN FOSSILS. 



1. Salysites catenularia, Linn., (sp.) ', Box Elder Canon. 



CAEBONIFEKOTJS FOSSILS. 



2. Zaphrentis; Bridger's Butte. 



3. Zaphrentis ? Stansburyi, Hall ; Eed Eock Creek, Twin Springs, 



Dry Creek Yalley. 



4. Lithostrotion ? 5 Twin Springs. 



5. Syringopora; liead of Alder Gulcli, Virginia City. 



6. Syringopora ; half-way between Mantua and Cache Valley. 



7. Bhomhopora ; Twin Springs. 



8. Chcetetes ; divide near Junction. 



9. Platycrnites fMucladocrinusJ Montanaesis, Meek. 



Body subovoid, a little higher than wide, the widest part 

 being above. Base basin-shaped, forming nearly one-third the 

 height of the body, rounded to the column below. First radial 

 pieces, a little longer than wide, with the widest part above, 

 oblong- subquadrangular in general outline, but having the 

 superior lateral angles apparently a little truncated, and the 

 lower edge convex in outline, while the upper margin has a 

 moderately deep sinus, equaling about one-third its breadth, 

 for the reception of the next radial. Second radial piece very 

 short, almost subtrigonal, with lateral angles a little truncated, 

 and bearing on its upper, sloping sides the first and only 

 divisions of the rays, which do not properly bifurcate again, 

 but continue like free, simple arms, composed each of a single 

 series of short, more or less wedge-formed pieces, every second 

 one of which gives off at its larger end (alternately on oppo- 

 site sides) a true arm. Arms very numerous, rounded on the 

 dorsal side, and composed each of two ranges of alternating 

 and interlocking small pieces that bear the pinnules (tentacula 

 of some) on their inner side. Surface smooth. (Vaalt un- 

 known.) 



This species is very i)eculiar in having the rays, after the 

 first division on the second radials, simple, or without further 

 division, and continued by a direct succession of a single 

 series of pieces. These divisions of the rays, although long, 

 free, and arm-like, are not true arms, because they each bear 

 on each side a row of arms that are, as usual in the genus, 

 composed of double rows of interlocking pieces, and support 

 delicate pinnules, or tentacles, on the inner side. It is proba- 

 ble that the ambulacral furrows of these divisions of the rays 

 are covered above by small pieces all the way out. If so, the 

 species would bear exactly the same relations to Platycrinitcs 

 proper, that Steganocrinus bears to Actinocrinites. Consequent- 

 ly, I propose to designate it as the type of a section, under the 



