Simpson — A Revision of the Gonionellidue. 287 



In 1905 Thomson and Henderson refencd several fragments from Ceylon 

 to this species. The axis was marked by longitudinal striae. In some the 

 verrucae were nearly 2 mm. in height, and the diameter of the axis was 

 1 mm. ; in others the verrucae were much smaller, and the diameter of the 

 axis was 2 mm. The spicules showed some variation from those in Kidley's 

 specimens. 



Juncella fragilis \ar. rubra. 



In the same paper Thomson and Henderson established a new variety, 

 namely, ruh-a, to include a long, flexible, complete colony, which tapered 

 gradually throughout its entire length. There was no trace of a lateral line 

 or groove. The verrucae were numerous and closely adpressed, measuring 

 about 1 mm. in height. 



From the above descriptions it is evident that this species has no definite 

 specific character. Eidley himself had doubts as to its distinctiveness ; but 

 its " simple " character at once separates it from J. gcmmacea. The specimens 

 from Mergui are undoubtedly J. juncca ; but Eidley practically acknowledges 

 this. I have examined the specimens described by Thomson and Henderson, 

 and although these undoubtedly coincide with the description of J. fragilis, 

 they also agree with young forms of J. juncca. A comparison of these 

 specimens and Eidley's descriptions, with the numerous colonies of various 

 ages which I was fortunate in obtaining at Mergui, proves beyond doubt that 

 this species was based on young stages of J. juncca, so that I would suggest 

 the merging of this species into J. juncca. At the same time the variations 

 in the different characters, as seen in these specimens, are of great interest, 

 and show how difficult it is to be certain of any species on a single or even_a 

 few specimens, especially if they are yoimg. The question of the size of the 

 verrucae and the presence or absence of bare spaces in this species is 

 discussed further on, so that it is necessary here to note only its relative 

 position in classification. 



Juncella flexilis Studer. 



This species was estabhshed by Studer for a small specimen (probably 

 young) with the following characters : — 



" The stem is simple, rising from a Hat base. The colony is only 

 20 cms. in height. The axis is thin and flexible, but contains lime 

 The polyps first arise at a level of 2 cms. from the base ; they occur 

 at first in two lateral rows, soon increasing in number, and occupying in 

 the upper part the whole surface of the stem. The verrucae are 2 mms. 

 long, are club-shaped, and are curved towards the stem. The coenenchyma 



B.I. A. PROC, VOL. XXVIII., SECT. B. [2 Q] 



