Geological Society, 



143 



Dimensions of tlie type (measured in tlie flesh) : — 



Head and body 190 mm. ; tail 170; hind foot 36 ; ear 23. 



Skull: greatest length 46''± ; coiidylo-incisive length 41'4; 

 zygomatic breadth 25; nasals 165; interorbital breadth 

 10*5; palatilar length 17 ; palatal foramina 3'8 x 2; upper 

 tooth-seiies (crowns) 7*6. 



Hab. Lamara>, Bahia, about 70 miles north of Bahia City. 

 Alt. 300 m. 



'fype. Adult male. B.M. no. 3.. 9. 5. 86. Original 

 immber 1508. Collected 16th Jane, 1903, by Alphonse 

 Robert. Presented by Oldfield Tliomas. Fourteen speci- 

 mens. 



''Inhabits the catinga forest/' — A. R. 



This subspecies differs from true albispinus by its less 

 rufous sides, its shorter broader-faced skull, and its more 

 proodont incisors. The hind foot of albispinus was described 

 by Geoffroy as being 45 mm. in length, but Dr. Anthony 

 informs me that this was an error, and that the hind foot of 

 the type oidy measures 38 mm. (c. u.), 35 mm. (a. u.), while 

 the two Geneva specimens also only have the hind fooc 

 36-37 mm. (s. u.). In this respect, therefore, there is no 

 difference between albispinus and sertonius. 



rilOCEEDINGS OF LEARNED SOCIETIES. 



GEOLOGICAL SOCIETY. 

 March 9th, 1921.— Mr. E. D. Oldham, F.R.S., 

 President, in the Chair. 



The following commuuicatiou was read: — 



' The Bala Country : its Structure and Rock-Succession. By 

 Miss Gertrude Lilian Elles, M.B.E., D.Sc, F.a.S. 



The lithological and faunal sequence is as follows : — 



Graptolitic 

 Shelly faunas. 



Cwm yr iEtlien Shales. 



faunas. 

 rZone of Monograptus 

 J crispus. 

 I Zone of Monograptus 

 1_ sedyivicki. 



Hirnant Grits and Mud- 

 stones, 300 feet, with local 

 I Hirnant Limestone. 

 [■ Moel-y-Ddinas Mudstones, 

 j about 250 feet. 



Moel-Frj'n Sandstones, at 

 ~| least 1000 feet. 

 I Rhiwlas Limestones and 

 [_ Mudstones. 



Orthis-hirnantensis', 

 fauna. 



Pliacops-niucronatus 

 fauna. 



Ph illi psinelln -para- 

 bola fauna. 



