1901.] NATURAL SCIENCES OF PHILADELPHIA. 337 



to the first gill-openiug from which it is separated by a consider- 

 able space. It is furnished with small pseudobranchiw, though in 

 moderate number. 



CEsophagm. — Constricted and somewhat short, the walls much 

 plicated. 



Stomach. — INIoderate and bulky, and the walls strongly plicated. 



Litesiine. — Duodenum the usual short simple tube merging into 

 the short and very bulky colon which is furnished with a spiral 

 valve. The rectum is a short simple tube, finally terminating in 

 the cloaca. A rectal gland is developed and confluent with the 

 rectum. 



Liver. — Large and bilobed, and with the left lobe the largest. 

 It is furnished with a gall-bladder. 



Spleen . — Presen t. 



Pancreas. — Present. 



DASYATID^. 

 17. Dasyatis brucco (Bonaparte). 



Trygon brucco Bonaparte, Fauna Italica, Pesci, Tomo III, VI, 1834, 

 34, PI. 151 (two figures). 



Nos. 378 and 379. Types of Trygon brucco Bonaparte. Italy. 

 Bonaparte Coll. (No. 218). Dr. T. B. Wilson. 



Mouth. — Moderate and broadly compressed. Teeth only upon 

 the jaws. Tongue absent. Superior l^uccal flap of almost uni- 

 form width and with a fringed edge. Inferior buccal flap entire, 

 except 5 or so filaments which are distributed at nearly equal dis- 

 tances. Integument of the inside of the mouth smooth and with- 

 out any shagreen. 



Pharyn.c. — Broad and compressed, and without any shagreen 

 patches, even upon the inner surfaces of the branchial arches. 

 Gill-openings 5, the median the largest, the second and fourth next 

 in size, and the first and fifth the smallest. They open into as 

 many gill-pouches and externally by as many gill-slits. Gill-fila- 

 ments in the usual continuous series in each gill-pouch, except in 

 the last, where they are only upon the anterior portion. They are 

 flattened or compressed, and aduate to the inter-branchial septa, 

 except distally for a very short portion, which is free. Aperture 

 of the spiracle superior and anterior to the first gill-opening. No 

 pseudobranchiffi appear to exist. 



(Esophagus. — Short and constricted with plicate walls. 



