RELATIONS OF SAGITTA BIPUNCTATA. 15 



without difficulty, at any rate in fine and calm weather, by 

 means of a small muslin towing net over the side of a boat. 



The animal, which has the form of a pointed needle, is 

 from one to two inches in length or less, and transparent as 

 the clearest glass. In warm, calm weather it swims on the 

 surface of the sea, and occasionally in the most surprising 

 numbers. In these latitudes it appears to be in a state of the 

 most complete maturity in August and September. 



The present account pretends to little originality, except 

 in the figures, some of which were made by myself in 1852, 

 from specimens taken in Sandown Bay in the Isle of Wight ; 

 and^ for others, I am indebted to [Mr. Huxley, whose observ- 

 ations upon this creature were made in the course of the 

 voyage of the ' Rattlesnake' in the seas of Australia. That 

 accurate observer, who has also studied the British form, is of 

 opinion that the Sagitta he examined in the southern hemi- 

 sphere and elsewhere, is identical with that found on our 

 coasts ; and I have, therefore, no hesitation in availing my- 

 self of his figures, illustrating the nervous system. 



The earliest notice of the animal which forms the subject 

 of this paper was given by Martin Slabber* in 1781, by whom 

 also the very appropriate name of Sagitta was applied to it. 

 This notice, however, seems to have been forgotten until 

 M.M. Quoy and Gaimard, when commencing their second 

 voyage round the world, re-discovered the animal, as it may 

 be said, in the Straits of Gibraltar. The species observed by 

 them was named Sagitta hijmnctata, and is probably identical 

 with that now under consideration. This form and other 

 species of the same genus have been since noticed and more 

 or less accurately desciibcu and figured by several authors, 

 amongst whom may be noticed Scoresby,t D^Orbigny,:f 

 Forbes,§ Darwin,|| Krohn,1[ Wilms,** Huxleyft and Busch.} j 



* ' Physikalische Behistigungen, oder mikroskopische Wahrnehmungen 

 von 43 in-und auslandischen Wasser-iind Landthierchen.' Nurnberg, 1781. 



t ' Account of the Arctic Regions,' vol. ii., Plate XVI. 



X ' Voyage dans TAmerique meridionale ; MoUusques, p. 140, Plate X., 

 figs. 1—7. 



§ ' Annals Nat. Hist.,' 1843. 



II ' Annals Nat. Hist.,' 1st Ser., vol. xiii., p. 1. 



ir ' Anatomiscli-physiologisclie Beobachtungen Ub. die Sagitta bipunc- 

 tata,' 1844. ' Nachtraglicbe Bemerkungen iib. den Ban der Gattung 

 Sagitta, nebst der Bescbreibung einiger neuen Arten.' (Wiegmann's 

 • Archiv.,' 1853, p. 266, Plate XII.) And Muller's ' Archiv.,' 1853, p. 140. 



* * ' Observationes de Sagitta, mare Germanicum circa insulam Helgo- 

 land incolente,' 1846. 



tt Report of British Association, 1851. (Trans, of Sections, p. 77.) 

 XX Beobachtungen Ub. d. Anatom. u. Entwicklung einiger wirbellos. 

 Seethiere, 1851, p. 93. ?l X V. j- > j I- i 



