ALCYOVARIA WHITELEGGE. 319 



broken off close to its origin, the other is 25 mm. in length and 

 ! mm. in diameter, diminishing to '05 near the apex, at a height 

 30 mm. it gives off a lateral branch, bearing two branchlets the 

 upper 45 mm. and the lower one 5 mm. in length. On the 

 opposite side at a height of 32 mm. from the origin of the first 

 branch is situated a second simple branch 42 mm. in length. 



The axis is laminate, calcareous, brittle and of dark brownish- 

 yellow at the base, with white or yellowish-white branches, the 

 basal portion of the stem is cylindrical, the branches are subquad- 

 rangular, without grooves, but marked by numerous elongated pits. 



The ccenenchyma is thin, and when viewed with a lens presents 

 a scries of minute ridges forming a network of raised lines, which 

 are lighter in colour and consist of double club shaped spicules. 



The polyps are large, alternate, arising at nearly right angles 

 and confined to the sides of the stem and branches, the verrucse 

 are conical, cylindrical or rarely wider at the base than at the 

 summit, varying according to the relative amount of the retraction 

 of the polyps within the verrucae. 



The verrucse are divided at their summits, into eight lobes, 

 each lobe is -3 mm. in height and -25 at the base. The verrucse 

 measure from 1- to 2- mm. in height, 1- to 1-5 mm. in diameter, 

 and are from 2 to 4 mm. apart ; the terminal polyps are slightly 

 larger than those on the stem and branches. 



The tentacles have a number of narrow fusiform spicules on 

 their dorsal surface, they are straight, and either distantly tuber- 

 culate or almost smooth. There are numerous rod-shape spicules 

 imbedded in the tentacles, they are arranged en chevron, their 

 surface is either smooth or minutely but distantly dentate. 



(1.) The cortical spicules are short double clubs with smooth 

 or warty tubercles. Size -05 by -02, -07 by -03, -1 by -05 mm. 



(2.) The ccenenchyma spicules consist of broad or narrow fusi- 

 form spindles, with rather obtusely pointed ends and a spiny or 

 tuberculate surface, some of which possess a transverse median 

 constriction. Size -1 by -03, -2 by -03, -25 by -05, -25 by -06 mm. 

 Many of the spicules, both clubs and f usiforms, are a little flattened. 



Colour in formol is light mouse gray. This species differs from 

 2f. dichntoma by its smaller more distant polyps and by its lax 

 method of branching. 



VERRUCELLA FLABELLATA, sp. nov. 

 (Plate xvii., figs. 34 - 37.) 



The only specimen in the collection is in a much broken condi- 

 tion, and evidently only a fragment of what formed an extensive 

 colony. 



