Simpson — A Revision of I Jw Oorgonellidm. 201 



111 the Cape and Mergui Collections are a number of colonies : (1) creamy 

 white, (2) pale orange, (3) bright orange, (4) ilull orange red, (5) lirick-red, 

 (G) pale orange yellow, with reddish tips to the verriicae. 



Scirpcaria flufjcllum. 



Monaco specimens: Dull white, creamy-white, pale yellow, orange 

 yellow. 



Naples specimen : The general colour of the colony is reddish orange, but 

 the tips of the verrucas are distinctly more reddish. 



On the whole, the colour schemes of Juncellids arc defined by the 

 coenenehyma proper and the verrueae, but in a few cases the colour of the 

 verrucae extends in streaks along the coenenehyma, and gives very pretty 

 tessellated patterns. Good examples of this are seen in some forms of 

 Scirpearia furcata (seiis. emend.) (see fig. 77). 



(2) Canal System. 



This is a feature to which little or no attention has so far been paid, but 

 which is of great taxouomic importance, and which also exerts a great 

 influence ou certain superficial appearances which have been used for 

 specific diagnosis. 



Deseription. — In all Juncellids it is essentially of the same type, and 

 consists of (1) an inner longitudinal series separating the inner canal-bearing 

 part of the coenenehyma from the axis, (2) an outer longitudinal series 

 separating the two divisions of the coenenehyma (see above), and (3) a 

 transverse series ramifying in all directions through the inner part of the 

 coenenehyma and uniting the two longitudinal series. 



This is common to all Juncellids (see figs. 10 and 13 of Juncella juncea, 

 fig. 19 of Juncella gemnmcea, fig. 25 of J. tnlineata, fig. 114 of JunccUa 

 quadrilincata, and fig. 43 of Scbpcaria pcctinata). 



As has been already remarked, the thickness of the coenenehyma is 

 almost a constant, and consequent upon this the thickness of the canal- 

 bearing parts separating these two series of canals is also a constant (see figs. 

 10, a, b, and c). 



With regard to the longitudinal series, it is essential to note that the 

 number varies in the ditt'ereut parts of the colony, or, in other words, diminishes 

 from the base upwards. 



We have made an extended study upon a large number of specimens, and 

 the following observations may prove useful : — 



1. The outer series of canals communicates directly with the polyps, and, 

 by means of the transverse canals, communicates with the inner series. 



