Benham. — On a Large Pterotrachczid. 247 



Snout. — Length from preocular "thorns" to mouth, 110 mm. ; 

 diameter at base, 20 mm. ; diameter just above buccal swelling, 

 10 mm. 



Ventral Fin.— Length of base, 45 mm. 



A comparison of proportionate sizes in my specimen and that 

 figured by Vayssiere, which measures 260 mm., shows a close 

 agreement. In the Pacific specimen the length of the snout 

 is contained two and a half times in the distance from preocular 

 thorns to genital fin, and in the Mediterranean specimen twice. 

 In the Pacific specimen the base of sucker is contained twice 

 in distance between it and snout, and in the Mediterranean 

 specimen twice. In the Pacific specimen the snout-diameter 

 to length is one-fifth, and in the Mediterranean specimen 

 one-fourth. 



Since these proportions agree pretty well, we may estimate 

 the total length of the uninjured specimen. Vayssiere states 

 that the distance from the visceral hump to the tip of the 

 " tail " (metapodium) is about twice the length of the fin- 

 base. Applying this to our specimen we should add 2 x 45 = 

 90 mm. to the above figure of 230 mm., giving a total length 

 of 320 mm. In the same way we may estimate the size of 

 the uninjured fin. Vayssiere's figure shows the length to be 

 rather more than twice the base-length, and height one and a 

 half times the base-length. So that the fin in our specimen 

 was probably about 90 mm. in length (i.e., a quarter of the 

 total length of the body), and 67 mm. in height. 



I have been unable to find any statistics as to the size of 

 the different species of Firola (Pterotrachea) ; neither in Bronn's 

 " Thierreichs " nor in the " Cambridge Natural History " do 

 any data exist. The " ' Challenger ' Report " gives only a list 

 of hitherto-described species, without details ; and, as I have 

 remarked above, the only species to a description of which 

 I can refer that approaches this one in size is P. adamastor, with 

 its 15 in., which measurement includes the length of the snout. 



As figures of the genus are not readily accessible in ordinary 

 text-books, I have deemed it advisable to give an outline of 

 my specimen, but with the missing portions represented in 

 dotted outline, copied from Vayssiere. I hope that people in- 

 terested in natural history will keep a look-out for this and 

 other unusual marine animals, and forward them, preserved in 

 formol, to me at the Otago University Museum. Formol is 

 obtainable at any chemist's, and should be used in a diluted 

 condition, by adding ten volumes of water to one volume of 

 formol. Animals placed in a bottle filled with this fluid, care- 

 fully corked, and packed in a small wooden box, or in shavings, 

 &c, and properly wrapped up, can be sent for a few pence by 



