i4 Bulletin 30 430 



Rissoina crassilabris Gabb. Tellina maoica. n. sp. 



Rissoina Sagraiana d'Orb. Merisca crystallina Chem. 

 Crucibulum cf. pileolum H. C. Lea. Merisca Sancti-Dominici, n. sp. 



Natica sulcata Born. Scissula cercadica, n. sp. 



Polinices subclausa Sby. Scissula scitula Dall. 



Sinum gatunense Toula. Strigilla pisiformis Linne. 



Bpitomium minutissimum Gabb. Psamrnacoma yaquensis, n. sp. 



Epitomium riparum, n. sp. Cyrnatoica hispaniolse, n. sp. 



Epitomium cercadicurn, n. sp. Psammosolen Sancti-Dominici, n. sp. 



Triforis Calypsonis, n. sp. Donax aequalis Gabb. 



Aclis acuminatoides, n. sp. Sanguinolaria Smithwood- 

 Melanella cercadica, n. sp. wardi, n. sp. 



Melanella maoica, n. sp Siliqua subaequalis Gabb 



Melanella jacululum, n. sp. Mactrella cf. alata Spengler. 



Melanella Tethyos, n. sp. Corbula cercadica, n. sp. 



Affinities of the Bhijf 3 Faima. — Of this list 24 per cent oc- 

 cur in Bluff 2, 23 at Bowden, 15 in Zone I, 13 in Zone H, 9 in 

 the Bulla river bluff, 9 in Zone G, 6 in Bluff 1 and 4 in Zone F. 

 The reciprocal percentages are 15 to Bluff 2, 7 to Bulla river, 6 

 to Zone I, 4 to Zone H, 3 to G, 2.9 to Bowden, 1 to Bluff 1, .92 

 to Zone F. 



The strongest bond is with Bluff 2 ; 1 and F are sharply set 

 off ; the tie with G is weak. 



Evidence of the Foraminifera. — Dr. Joseph A. Cushman has 

 very kindly identified the Foraminifera we collected. There are 

 in all 33 species, chiefly from the Rio Mao and Cana. Dr. Cush- 

 man writes that "in general Zones H and I, Rio Cana and 

 Bluffs 2 and 3, Cercado de Mao seem to represent a single unit 

 as far as the Foraminifera show and I should put the age of these 

 Early Miocene or Upper Oligocene, preferably the former." 



Thus Bluffs 2 and 3 are linked together and allied to H and 

 I by the "Foraminifera just as they are by the Mollusca. 



Dr. Cushman tells me that during the deposition of Bluff 2 

 conditions were evidently very favorable for Amphistegina 

 which is so exceedingly abundant. 



Apropos of the Santo Domingo Tertiary Foraminifera it may 

 here be mentioned that Gabb used "Orbitoides" as a very im- 



