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SCIENCE 



[N. S. Vol. LI. No. 1326 



possibly be contested. It is true tbat there 

 is in both forms a long shaft constriction. 

 But in Barosaurus the ischiatic contact is not 

 short, but long or rather deep, and concave 

 as in Apatosaurus. The type is in this 

 feature composite. In fact if a form uniting 

 features of the greater sauropods, including 

 the Camarasaurus, were sought, so far as 

 public features go, Barosaurus might well be 

 named. 



Regarding a prosimal femur fragment 

 which is found to far exceed the proportions 

 in Diplodocus, I may say that in no case is 

 the femoral size absolutely determinate as 

 large. The group of fragments from a Pied- 

 mont village " rock pile " or " fossil heap " 

 purported to come from the Barosaurus 

 quarry site. But only seven miles northerly 

 there was an exposure of a fast disappearing 

 Dinosaur bone bed several acres in extent. 

 Being all outside the frost line, the material 

 present in variety was much checked and 

 broken. So fragments of limb bones could 

 have been taken from this point to the 

 " rock pile " at Piedmont, mainly, if not ex- 

 clusively from the real Barosaurus outcrop. 

 Or again, if the record fails, it is to be re- 

 called that a second (though actually smaller) 

 dinosaurian was recognized by Marsh in the 

 material from the outer edge of the quarry, 

 as confii-med by Lull. The point is that if a 

 second form could so occur on the erosion or 

 quarry front, then there might also be a third. 

 A waterway, stream, or trend of some kind 

 is indicated. 



It is worthy of addition that in the Baro- 

 saurus quarry well inside the frost line, there 

 were various fragments of charred or car- 

 bonized wood passing into silicified structure. 

 Such material from the Morrison has not 

 been studied. Also, various pebbles of a 

 singular smoothness were noted at only one 

 point close to the main group of dorsals. As 

 the specimen was incomplete the reasonable 

 explanation that these were stomach stones, 

 or as later called, dinosaurian gastroliths, did 

 not then occur to me, their true character 

 being first recognized in examples from the 

 Big Horn mountains. 



Obviously Barosaurus lentus is a remark- 

 able dinosaur from several points of view. It 

 comes from far to the north and east of 

 the Wyoming localities, and shows the great 

 extent of the Como beds, as Marsh called 

 them. The parallel vsdth the African types 

 adds great interest to Barosaurus. As a 

 specimen it promised little of determinate 

 value after two months quarry work, and then 

 suddenly turned out to be, " except for the 

 lack of limbs, one of the finest of all Tale 

 specimens." The type remains somewhat 

 isolated because collecting along the inner 

 edge of the Black Hills " Rim," though never 

 hopeless, is always much limited by the long 

 talus slopes hiding the Morrison. This for- 

 mation encloses the Hills and the Bear Lodge 

 horseshoe-like, with the open heel on the 

 southeast from north of Builalo Gap to near 

 Minnekahta. On the west side of the HiUs 

 the maximum thickness of 200 feet is reached. 

 There, as further west in the Big Horn Rim 

 and in the Freeze Outs, is found the asso- 

 ciation of the smaller silicified cycads with 

 the sauropod Dinosam-s. And both in the 

 Morrison, and in the overlying Lakota, from 

 the lowermost strata of which comes the fine 

 cycadeoid Nilssonia nigracollensis, a long con- 

 temporary cycadophytan and dicotyl record of 

 the Comanchean is yet to be brought to light. 

 Reconnaissance in this important field is but 

 begun. 



G. R. WiELAND 



Yale TjNiVEESirY 



LOUIS VALENTINE PIRSSON 

 Professor of physical geology in the Shef- 

 field Scientific School of Yale University for 

 twenty-one years, after rapid promotion from 

 the position of instructor in geology and 

 lithology, to which he was appointed in 1892; 

 Professor Pirsson also occupied a position of 

 commanding importance in the administra- 

 tive work of the Scientific School, as member 

 of the governing board, and as assistant to 

 the director. Professor Chittenden, in matters 

 of discipline and general policy. An assistant 

 in analytical chemistry for six years after 

 graduation from the Scientific School, he 



