On a New Brachiate Asteroid Larva. 197 
slightly smaller than the corresponding right one. In this connection it is 
interesting to note that Bury’s figure of an intermediate Bipinnaria asterigera 
larva (2, pl. v. fig. 18) shows some reduction in size of the left postero-lateral 
and post-oral processes, particularly of the former. Shortening of the left 
postero-lateral is also a feature of Dr Ashworth’s specimens referred to 
above. 
The following measurements, etc., of the larva illustrated in Fig. 3 will 
be of interest :— 
Total length of specimen : : 3 HAD meiony 
Centre of disc to tip of anarm . f IER) i 
Length of preoral lobe from transverse portion of neeoral 
band to bifurcation into ventral and dorsal median 
processes ‘ Ones 
Length of ventral median process a aA ee 
Breadth of __,, si : ; ieed 3 eames 
Length of dorsal median process . IS) 9 3 
Breadth of a ke near extremity . ae ba ee 
os nA ie near base ‘ 5 dhodl 
Length of the ciliated processes, ¢.g., the posterior dorsals 2:0 _,, 
Twelve pairs of sucker feet are present in each ray. A hump dorsally at 
the base of the dorsal median process probably marks the anterior limit of 
the anterior ccelomic cavity. 
I have to express indebtedness to the Ivish Fisheries Department for the 
opportunity of examining the Echinoderm plankton material which contained 
the specimens described in this paper. 
REFERENCES. 
1, Acassiz, A. Embryology of the Starfish, Mem. Mus. Comp. Anat. Harvard, 
vol. 5, 1877, pp. 1-83. 
2. Bury, H. The Metamorphosis of Echinoderms, London, @.J.I/.S., vol. 
xxxvill., 1896, pp. 45-131. 
3. Devacr, Y. Hlevage des Larves Parthénogénétiques d’Asterias glacialis, 
Arch. Zool. Paris, ser, 4, vol. ii., 1904, pp. 27-42. 
4. Garstanc, W. On Some Bipinnarie from the English Channel, London, 
Q.J.MS., vol. xxxv., 1894, pp. 451-460. 
5. GemmiLL, J. F. The Development of the Starfish Solaster endeca, Forbes, 
London, Trans. Zool. Soc., part i., 1912, pls. 1-5, pp. 1-71. 
6. GemmiLL, J. F. The Development and Certain Points in the Adult Structure 
of the Starfish Asterias rubens, L., London, Phil. Trans. Roy. Soc., ser. B, 
vol. ecv., 1914, pp. 213-294. 
