406 PROF. J. A. TnOMSON ANB MR. W. D. HENDERSON ON [Apr. 10, 



to any of the known species. The average length of the con- 

 tracted polyp is 5 mm. 



The tentacles are short and l)luut, 1-8 mm. in length and 0'7 

 mm. in breadth. The pinnnles practically cover the whole surface ; 

 they are very small and wartdike, and are arranged in 6-8 rows. 

 No calcareous liodies ai-e to be seen, l)ut there are abundant zoo- 

 chlorellpe with a diameter of O'Ol mm. Many of the polyps show 

 abundant ova. The colour in life was described as " pinkish 

 brown with blue tentacles." 



It ma.y be unsatisfactory to estai)lish a new species for speci- 

 mens which have so few positive characteristics ; it seems to us 

 the most woi'kable way of finally ari-iving at a knowledge of the 

 relationships within this prolific genus. It must l)e left to some 

 one woi'king on the spot to I'edvice the number of species by dis- 

 covering the annectent forms. 



Locality. Near Kiungani, Zanzibar. 



Clavularia mollis, sp. n. 



The polyps of this i-ather puzzling form arise from a thin semi- 

 transparent membranous plate, 36 mm. long and 21 mm. in maxi- 

 mum width ; they seem to be crowded on the surface, but when 

 separated considerable spaces are seen between their bases. They 

 are ai-ranged in small gi'oups of 4-8, which are joined together 

 for a short distance from their base l)y the fusion of their walls. 

 But each polyp can be traced to its origin, and does not lose itself in a 

 stalk-like portion as in Xenia. Scattered between the groups small 

 single polyps niiiy be seen. The polyps are capable of considerable 

 conti-action, as some appear like siiiall teat-shaped papilhe on the 

 surface of the basal membrane. The oral opening of the polyps is 

 small and pore-like, situated on the smnmit of a teat-like papilla. 

 The tentacles are short, with slender pinnules arranged all round. 

 The stomodieum is short, measuring only 0-9 mm. in length l)y 

 0*2 mm. in breadth in an adult polyp. 



There are numerous ova in most of the polj'ps. 



This species is also represented by a badly-pieserved colony 

 40 mm, in length and 25 mm. in breadth. The stolon is smooth, 

 flat, and membranous. The polyps are 3 mm. in length, nearly 

 1'5 mm. in diameter, and are much contracted with numerous 

 annulations. The tentndes are nearly as long as the polyps 

 (2*7 mm.). The slender pinnules almost cover the tentacles, but 

 there is a bare aboral streak ; a common length is 0"5 mm. ; there 

 are 6 rows of aliout 15 in each row. In the basal poi'tions of the 

 polyps abundant ova are present. 



This form approaches in some ways Mny's (J.flava {non Hick- 

 son's C. ffava), but the pimiules ai'c thread-like instead of being 

 blunt, and there is no trnce of spicules. 



Locality. Zanzibar shore. 



Clavularia parviila, sp. n. 



A colony spreading upon a, stout*, the individuals united partly 



