366 Proceedings of the Royal Physical Society. 



In all three species the scales have a number of spinous 

 processes on their free margins, but the comparative strength 

 of these is not sufficiently constant to be of specific value. 

 Nevertheless, in each species there is a tendency for a par- 

 ticular form of scale to predominate. In all three species 

 the central spine is strongly developed. In Z. unimaculatus 

 there are three central spines much stronger than the others, 

 but of these the two lateral ones are usually slightly shorter 

 than that between them. In Z. j^uoictattcs the central spine 

 is very strong, and the lateral ones, none of which approach 

 it in size, become smaller and smaller towards the lateral 

 margin. In Z. papillosus the arrangement is similar to that 

 in Z. pu7ictatus, but all the lateral spines are so much 

 reduced as to exaggerate the importance of the central one. 

 Such is the typical scale structure of the species here 

 described, but it is easily possible to find intermediate forms, 

 which link the extremes together. 



1. Z. PUNCTATUS, Bloch. (PL XIV.j 



Plcuro7iectes punetatus, Bl. 

 ,, hirtus, Abilg, 

 Zcugopterus punctatus, Day. 



Fin formula (Day).— D, 87-101 ; A, 69-80 ; P, 10 ; V, 6 ; C, 14-16. 

 Fin formula (own specimens).— D, 97-102; A, 78, 79; P, upper, ^^ ; 

 loiver, iV ; V, 6 ; C, 16. 



The dorsal fin commences at the aiiterior margin of the 

 maxillae. The anterior rays are short, and not produced into 

 fleshy filaments as in Z. unimaculatus. The accessory por- 

 tions of the dorsal and anal, passing under the caudal, consist 

 of five or six much branched rays, and are not scaled. The 

 inter-orbital ridge is slightly raised and almost fiat, its dia- 

 meter being about one-third that of the eye. The eyes are 

 a little more than the diameter of the orbit from the tip 

 of the snout. A continuation of the posterior straight 

 portion of the lateral line would pass through the inter- 

 orbital ridge. 



The left pectoral is about twice the length of the right, and 

 reaches back to the curve in the lateral line. Each pectoral 

 has its first ray short and thick, that on the right side being 

 less prominent. 



