196 MICRURA FUSCA. 



proboscis are quite characteristic. The late Mr. Harry Goodsir mentions that, " when swimming, 

 the animal is very active, and advances with considerable rapidity by means of an undulatory 

 serpentine motion. When handled it throws itself into various contortions, and instantly casts 

 off numerous annuli from the posterior part of its body, each of which, immediately upon its 

 separation from the original, begins to move in a similar manner." Sir J. Dalyell afterwards 

 made like observations, and noted that the animal was full of a yellow substance, a remark which 

 probably applied to the wall of the digestive cavity, the same colour being present in Micrura 

 fusca. He also found numerous white ova discharged from a fragment in May. The Lineus 

 Beattim of Dr. Gray, and the L. longissimus of Mr. Beattie, appear to belong to this species, if 

 we may judge from the preparation of the former and the proboscis of the latter in the British 

 Museum. Mr. Alex. Agassiz mentions that he found the Planaria angulaia of 0. P. Miiller on 

 the under surface of the tail of Limutus, but of course this refers to quite a different form, probably 

 to a Planaria. 



This species is very closely allied to Micrura fusca; and if the structure of the proboscis had 

 not deviated so distinctly I should have been inclined to unite them. 



Genus VIII. — Micrura, 1 Mrenberg, 1831. 



As has occurred in several instances, the typical form was known to the veteran naturalist 

 0. P. Miiller, as well as to Col. Montagu. Ehrenberg, however, separated the genus from others 

 for the first time in his ' Symbolse Physical and gave a good figure of M. fasciolata, though he 

 was unaware that the same form had previously been observed by others. 



Generic character. — Body not much elongated. Head distinctly marked, snout truncated. 

 Other characters as in Lineus, with the addition of a caudal process or style capable of 

 attachment. 



1. Micrura fusca, n. s. Plate VI, fig. 3. 



Specific character.— -Eyes four to eight on each side, small. Body much flattened and 

 thinned at the edges ; speckled with brownish grains on the head and anterior region. 



Synonym. 

 1869. Micrura, Mcintosh. Trans. Roy. Soc. Edinb., vol. xxv, pt. ii, p. 376, &c. 



Habitat. — Not uncommon amongst the debris from the coralline ground in fishing boats, 

 amidst oysters and tangles in the laminarian region in Shetland, under stones between tide-marks 

 at Herm, and at a depth of 795 fathoms off the coast of Portugal. 



Body. — Two to four inches in length, slightly tapered towards either extremity, flattened both 



1 Macpbg, small or slender, and ovpa tail. Strickland applied the same title to a genus of Certhidas 

 in 1841 ('Ann. Nat. Hist/). 



