158 PEECY SLADEN TEUST EXPEDITION. 



Genus MURICELLA. 



A study of forms like Acis ohscura seems to us to show conclusively that in the 

 family of IMuriceids the genera Acis and Muricella are nearly related. It may he noted 

 that a characteristic feature of the genus Muricella is the way in which the verrucse, 

 with small vertical spindles, arise from hetween the large ccenenchyma spindles. 



36. Muricella complanata, Wright and Studer. (Plate 6. figs. 3, 8, 12.) 

 For description see : — 



Wright and Studer: 'Challenger' Report, xxxi. 1889, pp. 125-126. 



A numher of typical rose-coloured colonies of this well-known species. Some other 

 specimens illustrate the variahility of coloration in this species ; whitish, yellowish, and 

 pale pink forms are represented. 



Locality. Amirante (E 12 and E 9), 32 and 34 fms. 



A large rose-coloured colony with much flattened verrucas. 

 Locality. Seychelles (E 4), 39 fms. 



Previously recorded from Japan, 345 fms. ( Wright and Studer, 1889); Periya Paar and 

 West Coast of Ceylon [Thomson and Henderson, 1905). 



We have some hesitation in regard to a form with very large (2 mm.) spicules. It 

 is an upright colony, 8 cm. in height and 7 cm. in maximum hreadth. There is a 

 straight main stem with alternate branches. The general colour is greyish-white. 



As the species of Muricella have been multiplied exceedingly, and as the differences 

 hetween them are within a narrow range, it seems to us better to refer this specimen to 

 the M. complanata type than to try to define a new species. 



Locality. Salomon, 60-120 fms. 



37. Muricella purpurea, Whitelegge. (Plate 6. figs. 6 & 9.) 

 Eor description see : — 



Whitelegge : The Alcyouaria of Funafuti, pt. ii. 1897, pp. 315-317, pi. 17. figs. 2G-29. 



Two incomplete specimens, expanded in one plane, and of a deep red or purple colour, 

 seem to belong to this species. They difl^er, however, in having smaller spiciiles, the 

 largest of them averaging only 2 mm. in length, while Whitelegge gives dimensions up 

 to 55 mm. 



In some of the verrucse the spicules show a tendency to arrangement in eight double 

 rows, and eight marginal teeth are in some cases clearly seen. The operculum consists 

 of eight triangles of spindles, each triangle consisting of four to five converging pairs. 

 Below the opercular pieces there is a collaret of four or five rows of horizontal spicules. 

 There are some small red spicules longitudinally disposed in two rows on the tentacles 

 beyond the tips of the opercular pieces. The tentacles are very white, and show only 

 about six pairs of pinnules. 



