﻿ANNALS 



OF THE 



SOUTH AFEICAN MUSEUM. 



(Vol. XV.) 



1.— South African Crustacea (Part VII. of S.A. Crustacea, for 

 the Marine Investigations in South Africa). — By the Rev. 

 Thomas E. E. Stebbing, M.A., P.R.S., F.L.S., P.Z.S., Fellow 

 of King's College, London, Hon. Memb. New Zealand Inst., 

 Hon. Fellow Worcester College, Oxford. 



(Plates I.-XII. of Vol. XV. Plates LXV.-LXXVI. of Crustacea.) 



At various opportunities Dr. Gilchrist and Dr. P6ringuey have sent 

 me specimens of Macrura from South x\frican waters. I was in 

 hopes of being able to deal with the accumulated material in a single 

 essay. But it now seems expedient to offer the present contribution 

 as a first instalment of the report. There is some excuse for going 

 slowly. The literature of the subject has become voluminous, and 

 not infrequently the student is confronted with two opposite diffi- 

 culties, in having to guess what species was intended by an old 

 meagre description, and in having to weigh critically all the minute 

 distinctions of a modern elaborate one. When there are many speci- 

 mens at his disposal all superficially ahke, he has to guard against 

 overlooking important characters that may differentiate some of 

 them. When the specimen is unique, there is the torturing alterna- 

 tive of spoiling it for exhibition in a museum by dissection, or 

 spoiling it for any real use to science by leaving it intact. With 

 the extension of research the task of assigning specific names 

 becomes increasingly hard, as connecting links are discovered 

 between species and species, and the range of variability within 

 an acknowledged species is demonstrated. Of the South African 

 macruran fauna it is probably true that its members have very near 

 relatives in almost every part of the ocean. 



Six new species are here proposed, and two new genera, Hali- 

 poroides and Macropetasma. Further, the name Pomatochelidae is 

 substituted for the family previously called Pylochelidae, and for 

 the preoccupied names Sicyonia and Ogyris the new generic names 



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