354 KANSAS UNIVERSITY SCIENCE BULLETIN. 
elongate and slender, with the middle of the shaft only 
moderately contracted. The articular surfaces are well 
formed, and both bones were hollow, as was also, apparently, 
the humerus. The ulna is taken to be represented by the 
most posterior of the two elements, though the relations of the 
elements may have been reversed. 
The base of the left wing of an orthopterous insect, possibly 
allied to Paolia gurleyi Scudder, lies between the radius and 
the ulna. The nodule also contains impressions of plants, a 
portion of a frond of a Newropteris, and the impression of 
one of the Cordaites. Lying next the radius is a slender, elon- 
gate element, which may be a rib or a portion of a metacarpal. 
If a rib it indicates that the animal belongs among the Bran- 
chiosauria. The fragment is only one-half as long as the 
radius and is entirely too obscure to base any conclusions upon. 
The other characters of the specimen point quite strongly to 
its microsaurian affinities. 
The structure of the articular surfaces of the limb bones 
alone would indicate the microsaurian relationship of Hrpeto- 
brachium. It may be provisionally associated in the family 
Molgophide with such forms as Molgophis brevicostatus Cope, 
Molgophis (Pleuroptyx) clavatus Cope, and Molgophis macru- 
rus Cope, from the Coal Measures of Linton, Ohio. 
MEASUREMENTS OF THE TYPE OF ERPETOBRACHIUM MAZONENSIS MOODIE 
mm, 
engthotescapulak rela ctevstertencta casio leven toe ekerercd-iovers 14 
Distal! wwadthyy -92.o<:<e)s wyseeiw ooo case deo etsiereteyers eperasiats poke 6 
Proximaleearmecergrepeisel onl cic ietsneloucrekoresceiteletene reer ste 3 
Ibyenvnnay Gorden (2) soanosgconacusqsuoogcoconeD 24 
OGG OF INPIMERUEs oagso0a0 Coo oonadDOUDOOOSOCEO 25 
UA Oe Whis Gs ponotoonosoaonoosoosDouoosDUNSS 24 
iBvoparaellayeoisdh ooncgougpoodpo ocopduedanoUmOd0dcK 4 
Diameter othershattay-emiecieeteleicelerrarrielcrerercheratar= 2 
DistalliwadGhipemerroe ee cio ercieleieiotectalsver-tencteteiorore torr 3 
Ib Sayeaner OL? TEU, ooo gacnoconooADDooSaDUOCOOnO SAG 25 
Eroximalcwadthiereiciarrtsysicsisioler ite ieierel-loteloleieleietoia = 4 
DrametbersoLathesshachareprretecristeieiteleterietetereiecekt=t= 3 
Wiaidthrorsdistaluend cetereceie ates leteloreisletetieceincreveroret 4 
The type specimen is 799 (222) of Yale University Museum. 
Collected at Mazon Creek, Grundy county, Illinois. 
