REPORT ON THE CTRRIPEDTA. 41 



been observed in Australia. The latter specimen was taken in June 1874. Whether the 

 Cypris-larvse belong also to this species I cannot say with certainty; probably, however, 

 they do. 



Lepas australis, Darwin. 



Lepas australis, Darwin, Monograph Lepadidse, 1851, p. 89. 



An inconsiderable number of specimens of this species were found attached to a 

 piece of Laminaria (Durvillial) picked up by the log line in the South Indian Ocean. 

 There are three or four full-grown and numerous young specimens attached to the full- 

 grown ones, and to the surface of the Laminaria. 



The only difference worth noticing between the specimens described by Darwin ami 

 those brought home by the Challenger, consists in the greater size of the latter. 

 Darwin states that his largest specimen has a capitulum of one inch long (25 '4 

 mm.), whereas one of those of the Challenger collection measures no less than 

 33-6 mm. 



The species was taken between Stations 143 and 144, December 22, 1873, hit. 40° S., 

 long. 27° E., on floating sea- weed. 



According to Darwin this species is common on Laminaria throughout the whole 

 Antarctic Ocean. To this ocean it is confined, as far as our knowledge goes. 



Lepas fascicular is, Ellis and Solander (PI. I. figs. 5-7). 



Lepas fascicularis, Ellis and Solander, Zoophytes, 1786, Tab. xv. fig. 5. 

 „ „ Darwin, Monograph Lepadido?, 1851, p. 92. 



During the cruise of the Challenger from Japan to Sandwich, along the thirty- 

 fifth degree of latitude, great numbers of floating Lepadids were met with. A considerable 

 quantity of these were collected and preserved in spirits. Dr. E. v. Willemoes Suhm 

 (loc. cit., p. 132), recognised in this Barnacle the very variable Lepas fascicularis, Ellis and 

 Sol., which was described by Darwin. In his paper, published in the Transactions of the 

 Royal Society, which is chiefly devoted to the development of this species, he enters into 

 the discussion of the question, whether this Pacific form be really identical with the 

 Atlantic form, or must be separated from it as distinct. 



According to him, the only differences are seen in the mandibles and the 

 maxilla?. Whereas the ordinary number of the teeth in the mandible is five, in must 

 specimens he dissected there were six. "Sometimes, however, there are five on one 

 side and six on the other, showing that this difference has no constant value." Tin 

 difference is quite an imaginary one; on PI. I. fig. 5 I give a figure of the mandible of one 

 of the Pacific specimens of Lepas fascicularis. Von Willemoes Suhm would call this a 



(ZOOL. CUALL. EXP. — PART XXV.— 1883.) 



s 



