154 Transactions. — Zoology. 



examples, the proportion of length to breadth being from 

 100-72 to 100-65 in the former, 100-65 to 100-60-5 in the 

 latter. The pleura of the abdominal segments, measm-ed from 

 the hinge (figs. 1 and 2, /() to the termhial spine, are also, 

 as a rule, proportionately shorter in the African than in the 

 New Zealand specimens. But in both these characters the 

 examination of a large series of individuals shows a complete 

 gradation between those from the two localities. 



The Cape specimens were not in a sufficiently good state of 

 preservation to allow of a careful examination of the internal 

 organs. But I find that there is no difference of any importance 

 from the New Zealand form in the gills, the gastric skeleton, 

 the mouth parts, or the microscopic structure of the branchial 

 setse. 



In the sculpturing of the abdomen, on the other hand, the 

 examination of about a dozen specimens of all sizes and both 

 sexes from each locality has shown no intermediate stages. 



I conclude, therefore, that there are constant though slight 

 differences between the common New Zealand Palinurus and 

 P. lalandii from the Cape of Good Hope, and that Hutton's 

 name, P. edwardsii, should be retained for the New Zealand 

 species, P. lalandii being no longer considered as an inhabitant 

 of our coasts. 



The differences relied upon are, however, so small, that but 

 for the wide separation of the two localities one would hardly 

 consider them as of more than varietal importance. Mr. 

 Trimen informs me that P. lalandii " is confined to the western 

 (Atlantic) shores of the Cape, and does not occur even in False 

 Bay, immediately east of the Cape of Good Hope itself," and 

 it would certainly be a remarkable fact to find the identical 

 species reappear so far east as New Zealand. Haswell* states, 

 however, that P. edivardsii occurs both in Tasmania and St. 

 Paul's Island, two localities which help to bridge over the 

 distance between South Africa and New Zealand, and it is quite 

 possible that specimens from these places may be found to 

 furnish intermediate steps, and thus to necessitate the merging 

 of P. edwardsii in P. lalandii. 



In any case, the existence of a single species, or group of 

 closely-allied geographical sub-species, in South Africa, St. 

 Paul's, Tasmania, and New Zealand, is a strong argument in 

 favour of Hutton's theory t of an antarctic continent, from which 

 the great Southern land-masses were stocked. 



* Cat. of Australian Stalk- and Sessile-eyed Oruataoea. 

 t " N.Z. Journ. of Science," vol. ii., p. 1. 



