GEOGRAPHIC AND GEOLOGIC DISTRIBUTION 329 



I'l-oiu certain similar cliaractcr« m vertel)ra\ chevrons, and nWuT elements. 

 Of this genus Janensch says: "So far as can now l)e seen, the later in- 

 vestigations confirm FraasV view that (J. afncaiinx in its slriutuiv shows 

 distinct accord with the North American genus Di/i/nJnciis." 



The second gi'oup of Sauropods is still more remarkalile. in that it is 

 so verv similar to a certain Morrison type as to he referred to the same 

 genus, /Innhiiisiiiii IIS. proposed Uy Uiggs in 1!)04. 'Die memhers of this 

 genus ai-e descril)e(| as of extremely massive l)uild. with lore limhs etpial- 

 ing or exceeding the hind liinhs in length, with an imineiise body — as 

 the !)-foot rihs imply — and with cervical vertebra' which may exceed a 

 meter in length. The total length of these animals, judging fi'om the 

 Tendaguru estimateSj could not have heen much less than 100 feet.-' 

 Bmrhiosaiinis altitkorax is the American species, wliile the African hn-ms 

 are known as B. hnnuai, with an extraordinarily long neck and a humerus 

 from -.MO to 'lAo meters in leng-th ; and B. fransi. which was smaller, 

 with an u])per arm hone measuring hnt 1.70 meters. 



'I'lie third genus is l)icr(BOsauru.'< Janensch, having neck veriehi'ie of 

 modeiate length, with two high, completely separated spinous processes. 

 This pairing of the spines is continned hack over the dorsal region as 

 far as the rump. Bifurcated spines are not a unique feature. ;is I hey 

 are present in Bronfosaunis and Diplodocus, among other genera; hut, 

 nowhere, to my knowledge, are they carried to the extreme of s|)cciali/a- 

 tion seen here. The American genera in which these spines are paired 

 generally show more or less deep lateral depressions, pleiirocoeles, on 

 either side of the vertehral centra. l)ut these are lacking in the African 

 form. Two species of Picnrosdiinis have been described. IK Ikihsc- 

 iiiiiiiiii has fairly heavy hinder extremities, and the \ci'tcbi'a' of the back 

 and tail are strongly built: the femur, liowever, measures 1.2:! niel:ers 

 long, which indicates a comparatively small animal. P. saillcri has the 

 dorsal \('i1rhi'a' lighter and smaller, but with still highci- spines. 



I'mli'iilala. — Of Predentate dinosaurs there have l)een found two 

 species of StegosauridiP and one small Ornithopod form. The details of 

 structure are not yet announced, but the Stegosaurs, neitlier of which is 

 large, have a dermal ai-nior consisting of "very strong spines, compared 

 to which the bon\- plates seem almost to lose significance."' As the latter 

 are perhaps the most chai-acteristic feature of the genus Sterjosaiinis it- 

 self, the infei-eiice is thai the African forms are representations of a 

 different genus; but we must await the conclusions of Doctor Hennig, 

 who is describinu' them, before an opinion as to tluu'r affinities can he 



■' Doctor Matthew beUeves that these African forms probably did not much exceed in 

 .size those of America. 



