356 Canon A. M. Norman on Cucumarla Montagui. 



any more than to refer it to tlie young of C. Planci, Maren- 

 zeller, to which latter species it appeared to me more likely 

 to be referable *. 



As I told Mr. Pace in litt., when young specimens of 

 C. Montagui, say 14 mm. long, should be found having 

 spicules agreeing with those of the adult, my view that 

 B and C arc young forms of that species would require to be 

 reconsidered. 



The colours of the two forms are stated by Mr. Pace to 

 somewhat differ, but not materially. The podia are, he says, 

 more numerous and in two parallel rows in Montagui, but in 

 B and C so few as to appear in a single series ; this is a 

 strong point in favour of the latter being immature t' Again, 

 he writes: "In sp. I" (^= Montagui) " the test, being densely 

 crowded with spicules, is very tough and coriaceous, and its 

 surface is much wrinkled ; while in sp. 2 '' ( = my B and C) 

 " the surface of the body is extremely smooth and delicate, 

 marked only with transverse striai due to the encircling fibres 

 of the superficial layer." Here, again, is a difference such as 

 is usual and might he, expected between mature and immature 

 examples. 



But the main question still remains to be answered : On 

 what grounds do I presume to suggest that B and C, the 

 majority of the spicules in which have six perforations, are the 

 young of a species in which the number of perforations is 

 almost invariably four, and never six ? 



1st. In Montagui the plate-spieula form a dense regular 

 layer, over which are developed the campanulate 

 spicules, but in B and C the spicules are not disposed 

 in a layer. They are comparatively very few in 

 number, and are developed at different depths in the 



* The spicules of C. Phmci are fiprured by Jeffrey Bell, Cat. Brit. 

 Eehin. B. M. pi. ii. fig. 2 ; but it i.?, I think, obvious that there is an 

 error in the ccjnnecting-lines to figures on the plate, and that the three 

 bottom figures lettered a and also the feet-spicules lettered b on the 

 middle ot the plate, which are joined by connecting-lines with the 

 spicules of C. rianci, belong to C. Hyndmanni figured on the ,?ame plate, 

 tbe feet-spicules of which species are peculiarly characteristic. Specimens 

 in my collection have been examined from Trieste (cotype ti'om Von 

 Marenzeller), Naples (.specimens received many years ago, when the 

 Holothurians were not well known there, from the Zool. Stat., under the 

 names C. communis and C. doliolmn), Gairlocb, Firth of Clyde {Dr. D. 

 Hobertson). 



t It will be seen by my figure o (which, slightly magnified, was sent 

 to me by Mr. Pace, and is the largest specimen known to me having the 

 spicula of B) that tbe podia are in double rows, thus showing signs of 

 more mature growth. 



