612 Mr. C. T. Eegan on the 



so that the accompanying figures are to some extent 

 diagrammatic. There appears to be a complete cartila- 

 ginous cranium, whicli is rather broad and somewhat 

 depressed. The membrane-bones — parietals, frontaU, mes- 

 ethmoid, vomer, and parasphenoid — are thin. The cartilage- 

 bones — basioccipital^ supraocciptal, exoccipitals, epiotics, 

 })terotics, sphenotics_, prootics, alisphenoids^ and lateral 

 ethmoids — are for the most part separated from each other 

 by cartilage. The slender palatine is attached to the 

 anterior end of the vomer ; the pterygoids, quadrate, etc., 

 have no feature of special interest ; the opercular bones are 

 very thin, almost membranous. 



The post-temporal is simple, attached to the epiotic; its 

 lower fork is represented by a ligament. The coracoid 

 ossifications are widely separated by cartilage, on which the 

 four rather large radial s are inserted. The small separate 

 pelvic bones are remote from the pectoral arch. 



The basalia of the dorsal and anal fins are not connected 

 w^ith the neural and hsemal spines. 



The vertebral column comprises 70 vertebrae ; the ribs 

 are feeble and sessile ; the hypurals have a radiating 

 arrangement. 



The exact systematic position of the Icosteidse is uncertain, 

 but the great development of cartilage and the weakness 

 of the bones is evidently secondary, and there is nothing 

 in their organization to prevent the assumption that the 

 Icosteid?e represent a specialized and somewhat degenerate 

 development of the Perciform type. 



LXIX. — The Classification of the Stomiatoid Fishes, 

 By C. Tate Regan, M.A., F.R.S. 



(Published by permission of the Trustees of the British Museum.) 



The Stomiatoids are Teleostean Fishes of the order 

 Isospondjli (oi' Malacopterygii) ; they are oceanic, some 

 descending to considerable depths. They diff'er from the 

 Clupeoids in possessing photophores, which are usually 

 arranged in two series on each side of the lower part of the 

 body. The dentigerous maxillary enters the gape and is 

 firmly attached to the prsemaxillary. The ribs are attached 

 to short autogenous parapophyses which are inserted in pits 



