REPORT ON THE CIRRIPEDIA. 25 



fathoms, yet it must be granted that the number of true deep-sea species of Cirripedia 

 is very considerable. 



There are 17 species living at a depth of from 500-1000 fathoms. 

 12 „ „ „ „ 1000-1500 



7 „ „ „ „ 1500-2000 ,. 



4 „ „ „ „ 2000-2500 



3 „ „ „ „ 2500-2850 



Often two or even three species of Cirripedia were brought up with the same haul of 

 the dredge, as for instance : — 



At Station 146. — Scalpellum tenue, Scalpellum brevecarinatum, Scalpellum flawm. 

 135. — Scalpellum eximium, Scalpellum carinatum, Scalpellum elongatum. 

 184. — Scalpellum dubium, Scalpellum australicum, Scalpellum truncatum. 

 150. — Scalpellum recurvi rostrum, Balanus corolliformis. 

 204. — Megalasma striatum, Balanus tenuis, Scalpellum ruhrum. 

 214. — Scalpellum album, Verruca nitida. 



And this seems to prove that there are places where the circumstances are especially 

 favourable to the life of Cirripedia. 



The occurrence of Scalpellu m and Verruca in the great depths of the ocean coincides in 

 a striking manner with the palajontological history of these genera. However, I have not 

 been able to identify a single one of the recent sj>ecies with those described by Darwin, 

 Bosquet, and Reuss, in their palasontological memoirs. The fossil species of Verruca 

 resemble much more those of the same genus which at present inhabit shallow water 

 than those occurring at a considerable depth : the latter form together a very character- 

 istic division of the genus. With regard to the genus Scalpellum, the fossil forms and 

 those found in the deep sea have no doubt some features in common, yet I failed to 

 ascertain a single instance of specific identity. To a certain extent this fact is 

 explained by the very limited geographical distribution of the different species. With a 

 few exceptions, the species were met with only once. These exceptions are the 

 following : — 



Pcecilasma carinatum, n. sp., dredged off Culebra Island (West Indies) and off 



Ascension Island. 

 Scalp>ellum elongatum, n. sp., dredged off Tristan da Cunha and off East Cape 



(Auckland). 

 Scalpellum velutinum, n. sp., dredged in the Atlantic Ocean, off Cape St. 



Vincent, and in lat. 32° 24' S. long. 13° 5' W. 

 Scalpellum stroemii, Sars, dredged south of Halifax and ("Triton" Cruise) 



north of Scotland. 



(ZOOL. CHALL. EXP. — PART XXV. — 1883.) V>h i 



