August 15, 1902,] 



SCIENCE. 



267 



lesser number are suggestive of a Permian 

 aspect. Only a few species occur in the 

 Permo-Carboniferous of Nebraska, and at 

 least one of them is identical with a Per- 

 mian species from the Red Beds of Texas. 

 The Upper Coal Measure fish fauna of 

 Kansas is slightly more varied than that 

 of Nebraska, Dipnoans and Crossoptery- 

 gians being represented besides Elasmo- 

 branchs. Altogether, more than twenty 

 species of fish remains are known from this 

 region. 



Phylogeny of _ the Cestraciont Group of 



Sharks: C. R. Eastman. 



The family of Cestraciont sharks has 

 had a continuous existence since the De- 

 vonian, a range which is paralleled among 

 fishes only by the Ceratodus group of Dip- 

 noans. Some of the Devonian and Car- 

 boniferous forms {Protodus, Campodus, 

 Edestus, Helicoprion, etc.) were remark- 

 able for their great development of sym- 

 physial teeth, which became coiled without 

 being shed, but none of these specialized 

 genera are known to have survived the 

 Paleozoic. This family probably gave rise 

 to the Cochliodonts with inroUed crushing 

 teeth in the Middle Paleozoic, and to the 

 modern ray type during the Mesozoic. The 

 existing Port Jackson shark is the sole sur- 

 vivor of the generalized Cestraciont stem, 

 and special importance is attached to a 

 study of its embryological phases. 



On a Complete Skeleton of a New Creta- 

 cean Plesiosaur, Illustrated from Photo- 

 graphs from Mounted Skeletons: S. W. 



WiLLISTON. 



The Bacubirito Meteorite: H. A. Ward. 



Baeubirito is a small but very old min- 

 ing town situated on the Rio Sinaloa in 

 latitude 26° and in west longitude 107°. 

 The elevation above sea-level is some 2,000 

 feet. The meteorite is seven miles nearly 

 due south from there, near the hamlet call- 



ed Palmar de la Sepulveda. It was struck 

 by the plow of Crescendo Aguilar in the 

 summer of 1871. He soon uncovered 

 enough of its bright surface to satisfy 

 himself that he had foimd a silver mine! 

 Its surrounding is now a cornfield, with a 

 black vegetable soil of some two yards in 

 thickness. In this soil we found the great 

 meteorite deeply imbedded. Its surface 

 was but a little below the surface of the 

 ground. 



The general form of the mass seen from 

 the side was that of one ramus of a huge 

 jaw. The surface was entirely covered 

 with ' pittings, ' very regular in size, and 

 about two to three inches across, shallow, 

 but with well-defined walls. There were 

 no areas which showed the devastation of 

 deep rust; a fact due both to the dryness 

 of the soil and to the large alloy of nickel 

 in the iron. On one side there was a deep 

 crack, running horizontally through half 

 the length of the mass. At one end this 

 crack was too narrow to insert a knife 

 blade, at the other end it was nearly three 

 inches wide. Over the area the vegetable 

 soil was from three to four feet deep, while 

 below it was a porphyry rock, common in 

 this part of the country, much broken up 

 by natural cleavages and decomposed in 

 situ. 



Immediately around the meteorite we 

 had dug much lower, leaving the great 

 iron mass poised on a pillar or pedestal of 

 the undisturbed rock. It needed little me- 

 chanical aid to make the mass turn over. 

 Looking beneath it we found that its late 

 bed was a clean depression crushed into 

 the rock, with absolutely no soil between 

 it and the mass which had lain above it. 



The extreme measures of Bacubirito, for 

 so our meteorite from the first has been 

 called, are: 



Length 13 feet 1 inch. 



Width 6 " 2 '•" 



Thickness 5 " 4 " 



