Parker. — On a Specimen of Regalecus. 



25 



The length of the rays is as follows : — 



Crest, or "First Dorsal" 



As in most other carefully-described specimens, including 

 the two figured by Collett, the first ray is stout at its proximal 

 end (4 mm. in diameter), the next four — i.e., the remaining rays 

 of the first nuchal — extremely slender (about 1-75 mm.), and 

 those of the second nuchal stout, their thickness diminishing, 

 however, pari passu with their length, so that the last is of the 

 same thickness as the rays of the second dorsal. The reason 

 of this variation in thickness is apparent, when it is seen, as 

 described in the following paragraphs, that the rays of the first 

 nuchal are united to one another for about their proximal half 

 by membrane, while those of the second nuchal are free, except 

 at the base. 



The first ray is united by membrane to the second for at 

 least its proximal 34 cm., probably a little more — its distal 

 portion being fringed by a delicate wavy membrane, which 

 terminates in a simple point, and is continued into a very 

 narrow hand, edging the anterior face of the distal end of the 

 ray (fig. 2). The four following rays are similarly joined, the 

 vertical height of the uniting membrane diminishing progres- 

 sively in successive interspaces, from 34 cm., between the 1st 

 and 2nd rays, to 21 cm. between the 4th and 5th. 



The remaining rays — those of the second nuchal — are united 

 only at the base : how far is uncertain, the membrane being 

 torn, but probably between 2 and 4 cm. These rays are 

 all fringed posteriorly by a wavy membrane, which terminates 

 distally in a thickened lanceolate lobe (fig. 3), as described in 

 my former papers. These lobes were present on all the rays of 

 the second nuchal, except the 7th and 9th, the former of which 

 was damaged at the tip only, the latter broken off short. 

 Curiously enough, the 7th and 9th were the only two perfect 

 rays in the Moeraki specimen. The presence of a small but 



