()32 OeoIiHfi'cal Society. 



condition, the bones Winsf t]uit<? undistorttnl. Tho olavioular aivh 

 is lari^^e and well develo^Knl. beini; verv similar in type to the olavi- 

 oular aivhes of some Li^wer Liassio forms. It is suijijostiHl that 

 the ivtontion of this primitive eondition in this, and perhaj^s iti 

 some other Wealden Plesios;iurs, may In? the oonsequeneo of their 

 oomjiciratively-sheltered life in a tluviatile or estnarine habitat. 

 Similarly, in the ease of the Platanistidjv amons; the Whales, 

 analoiyous conditions of life seem to have led to the jx?rsistonee 

 of primitive eharaetei-s. 



it is pri>jK>sed that this new species of Plesios;\ur shall l>e made 

 the type of a new genus, LeptocIfiJ us, its sjxvitxe name being 

 Leptocleiifus siipersfes. 



The shoulder-girvlles of two species of Lower Liassio Plesio- 

 s;iui"s are also deserilxnl and figuivd, and the generic name £u fa- 

 ciei Jus is suggested for these, the type-species Wing Eu ri/clei- 

 (ius at'cuatus (Owen) fi-om the Lvnver Lias of Street (Somerset). 



LV • The CarlKMiifeivus Kocks of tho Poor- Like District of 

 Newfovmdland.' Bv Thomas Laudell-Mills, F. G.S.. Arthur Smith 

 Wixxlwanl, LL.D., F.K.S., Pivs.L.S., F.O.S..and Albert Gillican. 

 P.Se., B.Sc, F.O.S. 



The Carlxmifeivus ivcks form a synclinal tlcxuiv with its 

 longer axis tivnding north-east and south-west. Underlying 

 these is a limestone series of undetermined age (but pivlvibly 

 jx^st-Cambrian and pre-Carbonifeiv>us), which rests on highly- 

 foldcil gneisses and schists of An.'ha\^n age. 



A thick mantle of Pleistocene deposits covei-s the whole region ; 

 but dccply-tivuohcd valleys give gooil ex}xisuivs of the Carlnini- 

 feixnis ivcks. and tho following sequence has been dctennimxl : — 



,. , f Tho Humbor Grit Series, consisting of alter- 



I ppKK e ARBOXiTKKors- I ^^^^^ ^,^^^ ^^j conglomenitos. griUs saiid- 



2000 feet + I stone;. «uia maris. 



LOWKR CABBONiFKKOrs — f (2) UpiXT or Gn\r >;liales. 

 4000 feet (about) "1(1) L<.»wor or Ked Shales. 



Fishes and plant-rcinains txnnir abundantly at sevei-al horizons 

 in the Lower (.'arlxmifcixius shales, but no fossils have been foinul 

 in the Ujipcr Carlx^nifeivus. 



The minoi-alogioal constituents of those doixtsits show a remark- 

 able resemblanoo to those making up ivoks of similar age in tho 

 North of England. It is inferivd that the deposits on either side 

 of the Atlantic weiv derived fivm tho s;uno land-ujass. Tho fish- 

 ivmains from Deer Lsike. described by Dr. A. Smith "Wotxlwanl. 

 are all fragmentary ; but they seem to ivpresent throe six'cics 

 closelv related to those found in the Linver Carboniferous of 

 Scotland. A group of ribs with the caudal fin and scattered 

 scales belongs to a Dipnoan fish, which may l>c refenvd to a new 

 !>|iecies of I'ronemus. Some spoeimens of a Palaxmiscid fish are 

 surticiently well ]>rescrvcd to show that tluy belong to a now sjx'cies 

 of Eloiiichthi/it. OxhcY scattered Pahconiscid .<oalcs sccn\ to belong 

 to Sliadiii ichth i/g. 



