CEOMERIA. 



93 



CROMERIID.E. 



Margin of the upper jaw formed by the prsemaxillaries and the maxillaries ; supra- 

 occipital large and widely separating the very small parietals ; opercular bones well 

 developed ; symplectic absent. Body naked. Praecaudal vertebrae with parapophyses ; 

 ribs and epipleurals slender, the former sessile. Pectoral fin inserted low down, 

 folding like the ventrals. No postclavicle. 



A single genus. 



1. CROMERIA. 



Boulenger, Ann. & Mag. N. H. (7) viii. 1901, p. 415. 



Mouth small and toothless, inferior. Gill-opening narrow, lateral ; three branchio- 

 stegal rays. Body elongate, compressed, scaleless. Dorsal and anal fins short, on the 

 caudal portion of the body. Vertebrae 42 to 45 (28-30 + 14-15). Air-bladder long 

 and slender, extending along the whole praecaudal part of the body. 



In its elongate, naked body and the posterior position of the dorsal fin, the remarkable 

 fish named after Lord Cromer bears much resemblance to the Galaxiidae, of which 

 representatives occur in South Africa, and I first referred it to that family. But, 

 owing to its very small size, its anatomy could not be investigated without great 

 skill, and I therefore handed specimens over to Dr. H. H. Swinnerton, who very 

 kindly undertook the examination * which has enabled me to fix its correct position 

 in the system, resulting in the establishment of a special family in the Suborder 

 Malacopterygii. This has been settled by the discovery of the mesocoracoid bone, the 

 presence of which I had been unable to detect. The absence of this bone 

 differentiates the Suborder Haplomi, to which the families Galaxiidae and Kneriida? 

 belong. Dr. Swinnerton's investigations were made mainly by means of microscopic 

 sections and wax models, and his results are here reproduced, in abstract, together 

 with the figures drawn by him, rfter the definition of the species. 



* Zool. Jahrb.. Anat. xviii. 1903, p. 58. 



