THE DECAPOD CRUSTACEAIN^S OF WEST AFRICA. 



By Mary J. Eathbun, 



Second Assistant Curator, Division of Marine Invertebrates, 



This paper was prepared at the request of Prof. O. F. Cook, for the 

 help of collectors aucl students ou the west coast of Africa, aud it was 

 his iutentiou to publish it as an appendix to his report of work done 

 for the New York State Colonization Society. The preparation of that 

 report haviug been unavoidably delayed, it was thought best to publish 

 this portion while it is complete. The region covered extends on the 

 continent from Senegal to Portuguese West Africa, inclusive, or from 

 the Eiver Senegal at about 16° north latitude to the Eiver Kunene at 

 17° south latitude. It includes the fresh waters tributary to this coast 

 aud the islands in the Gulf of Ouiiiea, namely, Princes Island, St. 

 Thomas, and Eolas. 



A comparison of the ranges of the species found in this area empha- 

 sizes the relation of the fauna to those of America and Europe rather 

 than to the fauna of South and East Africa. Of the 152 species enumer- 

 ated, 40 occur also in some of the islands west and northwest of Africa — 

 the Azores, Madeiras, Canaries, Cape Yerde Islands, Ascension Island, 

 or St. Helena — 24 species have been recorded from the Atlantic coast 

 of America, 25 from Europe or the Mediterranean, 8 are South African, 

 5 East African, 6 extend to the west coast of America, while 15 occur 

 in the oriental region. The widespread species. Planes minutus, 

 Grapsus gra/psiis, and Pachygrapsiis transversus are excluded from the 

 foregoing count. 



More than half the species of the list are known to the writer only 

 from descriptions. Professor Cook and his colleagues have extended 

 the range of several species, and have added one, CUbanarius cooM, to 

 those hitherto known 



The classification used in this paper is chiefly, but not wholly, that 

 of Claus in the Grundziige der Zoologie. The key to families is made 

 up partly from definitions in that work, and largely from those in 

 Stebbiug's History of Crustacea. 



Proceedings U. S. National Museum, Vol. XXII— No. 1199. 



' 271 



