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II. Studies in New-Zealand Ichthyology .—1. On the Skeleton of Regalecus argenteus. 

 By T. Jeffery Pakkek, B.Sc. Lond., Professor of Biology in the University of 

 Otago, New Zealand. 



Received March 18th, 1884, read April 1st, 1884. 



[Plates II.-VI.] 



Contents. 



Page. 

 Introduction, including Systematic Description of the Species 5 



1 . The Cranium ' 



2. The Suspensorium and the Upper and Lower Jaws 14 



3. The Opercular Bones 1 o 



4. The Hyoidean Apparatus ^^ 



5. The Branchial Arches 1" 



6. The Vertehral Column and the Dorsal Fin 19 



7. The Shoulder-girdle and Pectoral Fin 26 



8. The Hip-girdle and PeMc Fin 27 



Summary 27 



Description of the Plates -^0 



The species Regalecus argenteus was founded on a specimen cast ashore at Moeraki, 

 Otago, in June of the present year (1883). On July 11th I read before the Otago 

 Institute a paper describing the specimen in detail, and giving a critical resume of the 

 observations of other zoologists on the various species of the genus. The paper will be 

 published in the nest (16th) volume of the ' Transactions of the New Zealand Institute ; ' 

 I extract from it, for convenience of reference, the following systematic description (see 

 PI. II. figs. 1-4). 



Regalecus argenteus, T. J. P. 

 D. 15/190. P. 13. V. 1. Br. 6. 



Height of the body about one tenth, length of head about one seventeenth of the 

 total length ,. Eye one sixth of the length of the head. Length and height of the 

 head about equal. The fifteen anterior dorsal rays form a crest, the height of which 

 is more than double that of the head ; its rays have their lower halves united by mem- 

 brane, their upper halves having a narrow membranous fringe ; more or fewer of them 

 terminate in lanceolate cutaneous lobes, and they are not spinose. Ventral rays fringed 

 posteriorly by membrane. No caudal fin. Four longitudinal ridges and an indistinct 

 fifth extend from head to tail above the lateral line, by which they are obliquely cut in 

 front. Surface studded with numerous hard but not bony tubercles, which are largest 



