CRUSTACEA MALACOSTRACA. IV. 



A comparison with the fauna of Norway and Great Britain may be of some interest, as the Mala- 

 costraca in the seas at these countries have been more thoroughly investigated than in any other area of 

 our globe. In his "Account" (1899 1900) G. O. Sars described 49 species from Norway, and of these 21 

 are unknown from the "Ingolf" area, but some among them will certainly be found there in the future. Of 

 the Cumacea of Great Britain and Ireland no complete faunistic list exists, but in looking over Stebbing's 

 work in "Das Tierreich" I found that the British fauna comprises 60 species, when "off Rockall" and the sea 

 between Rockall and Ireland is included; of these species only 22 are known from the "Ingolf" area. According 

 to the numbers given the seas around our northern dependencies have been proportionately rather well ex- 

 plored, though it is quite certain that many forms living in the warm area, and especially in depths from 

 300 to 600 fathoms, have not yet been discovered. 



On the Literature. 



On this topic very little need to be said. During the years 1899 1913 a series of very important 

 papers have been published by G. O. Sars, W. T. Caiman, T. R. R. Stebbing and C. Zimmer. In his book 

 on the Cumacea in "Das Tierreich", 39. Lief., 1913, Stebbing has compiled and quoted the whole literature 

 until 1912, and for this reason I have referred to his most useful book in the synonymical list at every species. 

 Zoologists wishing to get further knowledge on synonymy than the generally rather few references in the 

 present paper can easily find them in "Das Tierreich". Zimmer 's original contribution to the knowledge 

 of the northern fauna is of slight importance, but his paper on the Cumacea in "Deutsche Siidpolar-Expedi- 

 tion 1901 1903" Bd. XIV, Zool., VI, p. 438 491 (published in 1913) contains a very interesting chapter; 

 "Zirkumpolaritat und Bipolaritat" (p. 483 488), in which an outline of the classification of families and 

 genera followed by me is given, together with the number of species of each genus in the five climatic zones 

 of the oceans. 



Results and Questions. 



A. The Material. 



A comparison of the Cumacea from the "Ingolf" area with the world's fauna of the same order may 

 be of some interest. In 1913 Stebbing states to have enumerated 309 accepted and 23 doubtful species; of 

 the latter category the great majority will certainly disappear as unrecognizable for ever or synonyms, and 

 only a few species have been established since 1913. If we therefore put the total number of valid species 

 hitherto established to 315, we must be near the truth. Compared with that number 66 species from the "In- 

 golf" area is perhaps somewhat more than might be expected. 



The latest arrangement of families and their genera of the world's fauna is that published by Zimmer 

 in 1913; it differs rather little from that adopted by Caiman, and Caiman's arrangement differs somewhat 

 from that by Sars in 1899 1900. Zimmer accepted only 7 families, and it is very interesting that 6 of these 

 are represented in the "Ingolf" area, while of the seventh family, the Ceratocumidae, only a single species 

 is known. Yet it may be added that the large family Bodotriidae, which has very few species in the cold areas 

 of the ocean and numerous forms in tropical seas, is poorly represented in the "Ingolf" area, while the some- 



