(U2 PROCEEDTNG.^ OF THE NATIONAL MUSEUM. vol. xxvr. 



This description is from specimens obtained at Kobe and Nagasaki, 

 where it is abundant. 



Coasts of Japan, conmion southward. 



Dumeril unites the Japanese species with the European Squatina 

 aculeata^ while Dr. (iiinther unites l)oth witli Squatina Mjnathia. The 

 several species of tiiis genus, if really distinct, have 3'et to be defined. 



Order IV. BATOIDEI. 



THE RAYS. 



Gill-openings inferior, slit-like, 5 in number; spiracles present; no 

 anal fin; dorsal fins, if present, inserted on the tail; body typically 

 disk-like, broad, and fiat, the margin of the disk being formed by the 

 expanded pectorals; tail comparatively slender, the caudal fin small or 

 w^anting. Vertebrae cyclospondylous. With the exception of the 

 Raj!(l;i\ most or all of the ravs are ovoviviparous. 



{fSdrog^ a ray; eidog^ likeness.) 



a. Sarcura. Tail comiiaratively tliick, with 2 dorsal.s and a caudal fin; no serrated 

 caudal spine. 

 h. Snout not saw-like. 

 c. Electric organs absent; skin not perfectly smooth. 



d. Species ovoviviparous; young developed within body of parent; disk pass- 

 ing gradually into long, stout tail; pectorals not extending to snout. 



RlIINOBATID.E, XVII. 



(hi. Species oviparous; eggs deposited in quadrangular, leathery egg cases, 

 with a projection at each corner; disk abruptly contracted at base of tail; 



pectorals extending to snout Rajid.e, XVIII. 



cc. Electric organs present; a structure composed of honeycomb-like tulles 

 between pectoral fins and head; skin perfectlj' smooth . Narcobatid^, XIX. 

 aa. Masticura. Ta:il comparatively slender; dorsal fin single or wanting; back of 

 tail usually with a serrated spine. 



e. Pectoral fins uninterrupted, confluent arotmd snout; teeth small. 



DASYATIDiE, XX. 



ee. Pectoral fins interrupted, one portion forming detaclied appendages on 



the snout ("cephalic fins"). 



f. Teeth very large, flat, tessallated, tew in number.. Myliobatid^, XXI. 



ff. Teeth numerous, very small, flat or tubercular; size of body enormous; 



cephalic fins conspicuous, resembhng horns Mobulid.e, XXII. 



Fanidy XVII. KHllSOBATID^. 



GUITAR-FISHES. 



Shark-like rays. Trunk gradually passing into the long and strong 

 tail, which is provided with 2 well developed dor.sal fins, a caudal fin 

 and a conspicuous dermal fold on each side; disk not very broad, the 

 rayed portion of the pectoral fins not being continued to the snout; no 

 con.spicuous spines, the skin being nearly smooth, or with warty tuber- 

 cles; no electric organs. Warm seas; distinguished from the j^c/;'/^/.* 



