514 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.54. 



new, have been identified in the remains from both islands. A series 

 of these specimens, including the type of the new rail described be- 

 low, has been presented to the United States National Museum by 

 Air. George G. Heye, at whose direction the work of excavating these 

 middens was carried out. 



A detailed description of the collection follows. 



LIST OF SPECIMENS FROM ST. THOMAS. 

 PUFFINUS LHERMINIERI Lesson. 



A right ulna and a left humerus, both more or less chipped and 

 broken about the ends, are referred to this species. These bones are 

 somewhat heavier than those in the single modern skeleton available 

 for comparison, but are within the limit of individual variation. In 

 this genus, individuals of the same species often show great differ- 

 ences in the diameter and length of the wing bones — a fact that is 

 well shown in a good series of skeletons of Puffmus kuMii harealis 

 in the collections of the United States National Museum. There are 

 no other published records of the occurence of P. Iherminieri on the 

 island of St. Thomas. 



AESTRELATA, species. 



A left tibio-tarsus from St. Thomas belongs to a petrel of this 

 genus. In AEstrelata the cnemial process of the tibio-tarsus is short 

 and rounded while in Puflnus it is long and broad.^ The condyles of 

 the specimen in hand agree in size with those in skins of AE. hasitata. 

 It seems probable that it may represent either AE. hastitata (La- 

 fresnaye) or AE. diabolica (Lafresnaye).^ Skeletons of these forms 

 are not at present available so that definite comparisons can not be 

 made. No species of petrel has been recorded previously from the 

 island. 



SULA LEUCOGASTRA (Boddaert). 



The following bones of this booby are present in the collection: 

 A right humerus nearly entire, the shaft of a left humerus, a nearly 

 complete right coracoid, a left femur that lacks the inner condyle, 

 and a left tibio-tarsus with the proximal end missing. These bones 

 in Sula leucogastra may be readily distinguished from those in Sula 

 piscator upon careful comparison, and in some instances the differ- 

 ences between the two species are striking. This is true especially 

 in the case of the head of the femur. In S. leucogastra the femoral 

 head is globular with an irregularly grooved area marking the at- 

 tachment of the ligannentum teres. In B. 'piscator the head uf the 

 femur is distinctly flattened with a large rounded pit or depiession 

 frrmed to receive the distal end of the ligament. The tibio-t-j^rsus 



iSee Shufeldt, R. W., Ibis, 1916, p. 634. 



2 See Noble, G. K., Bull. Mus. Comp. Zool., vol. GO, 1910, pp. 370-374. 



