Dr. A. Giiuther on three new Trachinoid Fishes. 85 



The following closely allied species has long stood in my col- 

 lection as H. Planorbis, Lesson ; on mature consideration^ it 

 appears deserving of separation. 



Helix Cantoriana, Bens., n. sp. 



H. testa mediocriter umbilicata, tenui, depressa, orbiculato-conoidea, 

 lenticulari, oblique subarcuato-striata, subtus Iseviore, utrinque 

 lineis distincte incisis remotiusculis spiralibus decussata, fusco- 

 cornea, translucente, nitidula ; s})ira parum elevata, depresso- 

 conoidea, apice nucleato, obtuso, rubello, sutura inipressa, sub- 

 marginata ; anfractibus 5^, convexiusculis, ultimo carina mediana 

 obtusiuscula utrinque compressa munito, subtus comexo ; aper- 

 tura obliqua, subquadrato-lunari ; peristomate tenui, acuto ; umbi- 

 lico infundibuliformi. 



Diam. major 10, minor 9, axis 3g mill. 



Habitat in insula Pulo Sung- Sung, props Pulo Piuang. Detexit 

 Dr. J. E. Cantor. 



A single specimen was found on the little island in question 

 by the late zealous zoologist Dr. Cantor. It is certainly distinct 

 from H. Sanis; and the peculiar sculpture, independently of 

 other characters, affords good ground for distinguishing it from 

 the recorded species of the same group. 



Including two Spiraxes, one of which is not in a sufficiently 

 perfect state for description ; a Bulimus, which appears to be the 

 young of the widely spread B. gracilis, Hutton ; a Helix as yet 

 undetermined ; an Auricula ; a Melampus, and a Pijthia, we have 

 now sixteen species of land-shells from the Andaman Islands. 



Cheltenham, Dec. 21, 1860. 



XII. — On three new Trachinoid Fishes. 

 By Dr. Albert Gunther. 



[Plate X. A.] 



The family of the Trachinida, Gthr., has been established for 

 those Acanthopterous Fishes which have the spinous portion of 

 their dorsal fin much less developed and shorter than the soft, 

 the anal fin similarly developed to the soft dorsal, and the ven- 

 trals composed of one spine and five rays. Their gill-openings 

 are wide, and the caudal portion of their vertebral column is 

 formed by many more vertebrae than the abdominal *. 



Such are the positive characters by which they may be easily 

 distinguished from the Sciceiiida, Carangida, Blenniida, Gobiidce, 

 Trichonotidce, &c. ; whilst the negative character, that of the 

 absence of an infraorbital bone joined to the prfeoperculum, 



* Gunth. Acanthopt. Fishes, ii. p. 225. 



