ALCVONAKIA. 393 



to one another. The younger branches and twins often present a pinnate appearance, 

 which is sometimes disguised by a larger development of one of the branches. The 

 stem and branches are flattened in the plane of branching, and the tips of the twigs 

 form blunt broad expansions due to the two divergent terminal polyps. 



The polyps are more or less contiued to the lateral edges of the branches; they are 

 all withdrawn, lint their tentacular portions are yellowish in colour. 



The spicules vary in length from 0"9 millim. to 1"65 millims., and in breadth from 

 Oi millim. to 0'2 millim. 



The colour of the colony is a deep coral-red ; and the spicules of the ccenenchyma 

 are visible to the naked eye. 



The specimen presents close resemblances both to Muricella perramosa and 

 .1/. nitida, but because of the greater resemblance in the arrangement of the polyps 

 and the more marked coral-red colour, it was thought best to place it under 

 M. riit Ida. 



Locality : Ceylon seas. 



Muricella coinplanata, Weight and Studer. 



This species is represented by a fragment of a colony, consisting of the lower part 

 of the stem with basal attachment, and a branch bearing secondary branches or twigs. 

 The basal attachment consists of a slightly conical spreading portion, from the 

 summit of which the stem arises. The stem measures 2'2 millims. near the base, and 

 at a distance of 11 millims. from the base the first branch, which is represented by a 

 fragment, was given off. The secondary branches or twigs are given off at right 

 angles, and may reach a length of 25 millims. to 37 millims. 



The polyps are arranged on the lateral edges of the stem and branches, and are 

 directed some to the front and some to the back. On the whole they are arranged 

 alternately, but this is not quite constant. The polyps measure 0"95 millim. in 

 height by 074 millim. in width, and are contained within verrucse which measure 

 0"35 millim. in height by 0"8 millim. to 1 millim. in width at the base. 



The stem is of a violet tint with yellow polyps and verructe, but this tint gives 

 place gradually on the twigs to an orange-yellow. The tips of the twigs end in two 

 divergent polyps, and this expansion measures 3 millims. in width. 



The spicules of the ccenenchyma vary in length from 07 millim. to 1'3 millims., and 

 in breadth from 0"1 millim. to 0*16 millim. They are straight spicules covered with 

 warts. 



This specimen, though not agreeing with Muricella complanata in every detail, 

 may be included in this species, which is variable in the colour and the size of its 

 spicules. 



We studied a second specimen of a more pronounced violet colour and with much 

 larger spicules. It was a complete colony which is attached to a piece of coral, and 

 measures 68 millims. in height and 53 millims. in maximum width. The basal 



