422 PROF. J. A. THOMSON AND MR, W. D. HENDERSON ON [Apr. 10, 



The main stem gives off elongated conical branches, and these 

 bear, especially on their lateral surfaces, numerous finger-shaped 

 lappets covered with polyps. 



The Stiltzbiindel consists of 5, 6, or 7 straight warty spindles ; 

 the polyp-stalk is covered by regularly arranged closely-fitting 

 small spindles ; the anthocodia; are at right angles to the Stiitz- 

 biindel and are directed inwards towards the geneial surface of 

 the colony. On the anthocodia there are eight double rows of 

 ten to twelve spindles in each row ; the opposite spindles in the 

 double row converge and the whole double row tends to stand out 

 like a ridge on the surface. There is no sign of spicules on the 

 tentacles. 



This species resembles iV. cupressiformis Kiikenthal in general 

 appearance, but the polyp-beai-ing lobes are more finger-like, and 

 both the general spicidation and the architecture of the antho- 

 codife are quite different. 



Locality. Wasin Channel, 10 fathoms. 



Nephthya zanztbarensis, var. mollis, nov. (Plate XXVII. 

 fig. 5.) 



A somewhat flattened whitish-grey colony, 7 centims. in height 

 by 3'5 centims. in maximum breadth and about 1 centim. in 

 thickness. At a short distance from the base it gives off a strong 

 side branch, and both it and the main stem bear numerous elon- 

 gated finger-like lobes or secondary branches bearing these. 

 Almost all the bi^anches and lobes are developed to the sides. 

 The colony is soft and flaccid, but the general coenenchyma is 

 covered with a feltwork of transversely-disposed colourless spiny 

 spindles (0"2 to 0'9 mm. in length) which give it an almost 

 striated appearance. No other type of spicule was to be found in 

 the colony. 



The pol}^3S stand almost at i-ight angles to their short stalks ; 

 the Stiitzbiindel is composed of about four to six straight spindles 

 (0"75 and 1-25 mm. in length), one of which projects for about 

 0'25 mm. The anthocodia is supported by eight double rows of 

 abovit ten spicules in each row. 



This form is characterised by the absence of the iri'egular 

 superficial layer of .spicules and by its darker colour, so that we 

 feel justified in making it a new variety. 



Loccdity. Wasin Channel, 10 fathoms. 



Nephthya armata, sp. n. (Plate XXYII. fig. 4.) 

 A stiff colony of a drab-grey colour, 3'5 centims. in height, 

 3*5 centims. in maximum breadth, and 2 centims. in thickness. 

 A short trunk bears five main branches, from which arise numerous 

 blunt and short finger- like lobes. 



The polyps are not densely crowded, but form an irregular spiral 

 on the lobes. In every case the month is turned inwards. There 

 is a well-developed )Stiitzbundel, often with four strong spindles and 

 sometimes projecting for about 0-5 mm. The Stiitzbiindel spicules 



