Gatty Marine Laboratory , St. Andrews. 105 



gated (PI. IT. fig. 3), and the prominent median lobe of the 

 toot appears behind the cephalic region. 



Somewhat later, viz. on the 18th February, 1898, two other 

 stages, apparently of the same form, occurred. The younger 

 has a bifid snout, a cephalic, a median, and a terminal ring of 

 cilia (PI. II. fig. 4). Each half of the bifid snout is 

 rounded and flattened, with palpocils at the tip. From the 

 dorsal surface the outline is quite symmetrical, but when 

 viewed laterally (PI. II. fig. 5) a lamellar process on each 

 side and behind these an awl-shaped process like a tentacle 

 are apparent. Such probably represent the median and 

 lateral lobes of the foot. The epipodia are not yet visible. 

 The central region is opaque whitish. 



In the same net on the latter date a further stage (PI. II. 

 fig. 6) was met with. It measured 1'257 millim. in length 

 and had a pinkish streak in the centre. The lateral fins were 

 now fairly developed, so that they were useful to the animal 

 in swimming, while the median and posterior rings of cilia 

 were still present. When the proboscis was evaginated the 

 radula formed a bluntly conical hispid process, and the widely 

 diverging hook-sacs ("jaws " of Eschricht, olim "fore foot" 

 of Ray Lankester) occupied each lateral region. The slightly 

 curved spinigerous processes of all these organs projected 

 freely, and even at this early stage seemed to be well adapted 

 for a predaceous existence. 



2. On Bipinnaria asterigera, M. Sars (Larval Stage of 

 Luidia), at St. Andrews. 



In his ' Beskrivelser og Iagttagelser ' the able Norwegian 

 naturalist Michael Sars presented in 1834 a series of rare and 

 remarkable animals from the waters adjoining Floroe, where 

 he then resided. Amongst forms ranging from polyps to 

 chordates there was none more novel than the larval starfish 

 which he describes and figures under the above name *. He 

 characterizes the genus as having a long, cylindrical, flattened 

 body, with two pinna? — one posterior, cordate in shape, and 

 another, somewhat triangular, in the middle of the body. 

 The mouth is surrounded by a series of lanceolate appendages 

 or arms. He distinguishes the species by the fact that there 

 are twelve arms. His figures show a somewhat more elon- 

 gated outline and narrower arms than the form at St. Andrews. 

 Sars procured his examples in the month of May amidst other 

 pelagic organisms such as Medusas. 



Koren and Danielssen j", in October 1846, had the good 



* Op. cit. p. 37, pi. xv. figs. AOu-d. 



t Ann. d. Sc. nat. 3 e stir. vii. p. 347, pi. vii. figs. 7-9. 



