BY J. DOUGLAS OGILBY 183 



more numerous and of larger size. The second character 

 brought prominently forward in Dr. Giinther's description 

 is the comparative distance between the dorsal fins, which 

 is stated by him to be " equal in length to the base of the 

 first dorsal" in G. harhatus^ and "much less than the 

 length of the base of either dorsal '^ in C. tentacidatus. 

 This character is entirely fallacious ; there is now before 

 me a specimen of an undoubted C. barbatus, from Port 

 Jackson, in which the intra-dorsal distance is quite as 

 small as in our example of C. tentaculatus, being but little 

 more than one-balf of the length of the base of the first 

 dorsal ; and further among specimens of the former of both 

 sexes and all sizes up to seven feet I have not found a 

 single example in which the intradorsal space was even 

 approximate in length to the base of the anterior dorsal. 

 The colours are also very variable, and are probably 

 similar in both forms, C. barbatus being as often as not 

 broadly fasciated with brown. The characters therefore 

 on which Drs. Peters and Giinther rely for the specific 

 separation of the two forms are thus proved to be 

 inconstant, and so absolutely valueless from a scientific 

 point of view. We have therefore to look for other 

 characters by which to separate the two supposed species, 

 and these I am unable to find, for if we except the 

 slightly finer granulation of the epiderm, there is positively 

 no character on which reliance can be placed. Our speci- 

 men, however, has very distinct hard tubercles on the dorsal 

 surface forming either scattered patches or irregular longi- 

 tudinal rows, as well as a crescentic row of much smaller 

 ones above the eyes, a similar row between the orbit and 

 the anterior gill-opening, and some scattered ones on the 

 snout and cheeks. As, however, neither its describer nor 

 Dr. Giinther makes any reference to these tubercles it is 

 probable that this is either an individual peculiarity — the 

 varieties of Chiloscyllium indicum form a fairly parallel 

 case— or was caused by the specimen having been left on 



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