l08 PEES1DENT*S ADDBESfe. 



Davidson, was dredged by the ' Challenger ' in the middle of the 

 Pacific at the vast depth of 2,900 fathoms, and twice on Eed 

 Clay. 



PoiYZOA. — Polyzoa are found at all depths, but almost all the 

 species belong to the Chilostomata, the orders Cyclostomata and 

 Ctenostomata being scarcely represented beyond 1,000 fathoms. 

 The genera which descend deepest are Catenaria, Cellularia, Meni- 

 pea, Nellia, Canda, Bicellaria, Bugula, Kinetoshias, Farciminaria, 

 Flustra, Carhasea, Salicornaria,, and Bifasciaria. Kinetoshias is 

 a very beautiful form, allied to Bugula, and is synonymous with 

 Naresia of "Wyville Thomson. Four species are known — K. 

 Smittii, Danielssen, first found in 80 fathoms in Nordland, and 

 afterwards in Kors Fiord, Norway, in which latter locality I 

 dredged a fragment in 1878 in 200 fathoms; K. arhorescens, D. 

 (= Bugula umlella, Smitt), recorded fi'om 90 fathoms, Yadso, by 

 Danielssen, and from 40 fathoms, Spitzbergen, by Smitt ; and a 

 third specimen, which was dredged during the Canadian Grovern- 

 ment investigations on the Eiver St. Lawrence, has been sent 

 to me for determination by Mr. Whiteaves. The ^Challenger'' 

 abyssal forms are K. cyathus, Wyv. Thomson,'^' which was dredged 

 in 1,525 fathoms, south-west of Cape St. Yincent, and afterwards 

 in 2, 650 fathoms, in the latitude of Buenos Ayres ; and K.ioocillum, 

 Busk, procured in 2,160 fathoms, near the Azores. 



Ckustacea. — I am not aware that any Brachyurous Crustacea 

 have been recorded as found below 1,000 fathoms, although, 

 since many species such as Ehalia nux, JN^orman, Amathia Carpen- 

 teri, Norman, Ethusa granulata, Norman, Lispognathus Thomsoni, 

 Norman, Homolopsis rostratus, A. Milne Edwards and others are 

 known to descend to 500-700 fathoms, they might reasonably be 

 expected to be found living at greater depths. Macroura are 

 remarkably abundant in the greatest depths, and are represented 

 by very distinctive genera, including the family ErgonidcB, which 

 has been already referred to. In 500-2,000 fathoms, Mysidea, 

 Cumacea, and the interesting family Munnopsidse (Isopoda remi- 

 gantia of Sars) abound, but on account of their small size and 



* Figured in Voyage of the • Chalk'iujer: — The Atlantic. Vol. I., p, 143. 



