170 BULLETIN OF THE 



Trigonorhina exasperata. 



This is the species described by Jordan and Gilbert under the name Platy- 

 rhina exasperata, and from which at a later date these authors drew the charac- 

 ters for the genus Zapteryx. The latter does not seem to differ from the genus 

 Trigonorhina of Midler and Henle. The species T. exasperata and T. alveata are 

 closely allied. 



The genus Platyrhina is closely related to Trigonorhina, and with it belongs 

 to the family Bhinobatidce. Both genera have broad based tubercles in a verte- 

 bral series and on the shoulders. Sympterygia and Platyrhina have little or no 

 affinity for each other. Of the Bhinohatidm the latter is, perhaps, the nearest 

 approach to the Rajce. It is out of place with the Bajidoe, as located by Du- 

 meril and Giinther. 



Trygon lata n. sp. 



Disk quadrangular, one fourth wider than long. Anterior margins nearly 

 straight, forming a very blunt angle at the snout, rounded near the outer ex- 

 tremities ; posterior convex; inner straight a portion of their length. Yentrals 

 truncate, rounded. Snout produced, forming a rounded prominence in front 

 of the margins of the disk ; length from forehead less than the width of the 

 head. A line joining the wider portions of the disk passes nearer to the head 

 than to the shoulders. Tail more than twice as long as the body, subcylindri- 

 cal, without a trace of keel above, roughened with small tubercles, with an 

 irregular series of broad-based conical tubercles on each side ; a long narrow 

 cutaneous expansion below has its origin opposite that of the spine, and ter- 

 minates in a keel which continues to the extremity. A pair of large com- 

 pressed erect tubercles stand immediately in front of the caudal spine, and a 

 single one is placed over the middle of the pelvic arch ; these suggest a con- 

 tinuous series in larger specimens. Three larger elongated tubercles with 

 points directed backward — similar to those of hastata — occupy the middle of 

 the shoulder girdle. Mouth curved, six (5-6?) papillae at the bottom ; two 

 of these are in the middle in. front where usually there is but one. 



Color light olive, probably greenish in life, white below. Distinguished 

 from T. centrura by the prominent snout, the shape of the tubercles on the 

 middle of the back, and the narrowness of the posterior portion of the disk. 



Length of body 16, length of tail 35.3, and width of pectorals 20.5 inches. 

 Collected at the Sandwich Islands by Andrew Garrett. 



Trygon longa n. sp. 



Disk quadrangular, about one sixth wider than long. Margins nearly 

 straight, anterior meeting in a blunt angle on the end of the snout. Outer 

 angles rounded, posterior blunt. Ventrals rounded. Tail more than twice as 

 long as the body, roughened with small asperities, depressed anteriorly, com- 

 pressed behind the spine, keeled above the compressed portion, with a long 

 narrow cutaneous expansion on the lower side. Mouth curved, with five 



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