Pakker. — Remarks on Palinuriis. 153 



P. edwardsii; or, in other words, the diagnostic characters 

 hitherto rehed upon having broken down, are there sufficient 

 differences from the Cape species to entitle it to retain a 

 distinct specific name ? 



After a careful comparison, by means of drawings and mea- 

 surements, of the series of New Zealand and African specimens, 

 I find that there is one constant and reliable difference between 

 the individuals from the two localities : It consists in the 

 greater complication of the sculpturing or tuberculation of the 

 abdominal segments in the Cape form. 



The difference to which I refer will be apparent from a 

 comparison of figs. 1 and 2, which represent the first and third 

 abdominal segments of a New Zealand specimen, with figs. 3 

 and 4, which show the corresponding somites of a Cape speci- 

 men of about the same size. 



In both cases, the first segment is marked by a strong trans- 

 verse groove {[/), which divides it into a larger anterior and a 

 smaller posterior portion, the former being covered by the 

 carapace in the extended condition of the abdomen. In all the 

 Cape specimens which have come under my notice the segment 

 in question shows a double row of tubercles (fig, 3, t) anterior 

 to the groove ; while in New Zealand specimens the anterior 

 section of the somite is either wholly devoid of tubercles (fig. 5), 

 or presents one or two very small detached ones (fig. 1). 

 Further, in the Cape crayfishes, the postei-ior section of the 

 same segment bears two rows of flattened squamiform tubercles ; 

 while in the New Zealand form there is only a single row of 

 imperfectly- formed tubercles. 



Similar differences are found in the remaining abdominal 

 segments, which show the same separation into anterior and 

 posterior areas, the groove (figs. 2 and 4) being, however, less 

 clearly marked than in the first. In the Cape specimens 

 (fig. 4) the tubercles on the anterior division are very numerous, 

 only a small portion of the segment being without sculpturing ; 

 in New Zealand specimens (figs. 2 and 6), there are only two 

 or three rows, so that fully half the tergum is left bare. In 

 the posterior area of the 2nd-5th segments there is a close 

 agreement with the corresponding region in the first, the Cape 

 specimens (fig. 4) having about two rows of tubercles ; the New 

 Zealand specimens (figs. 2 and 6), a single row of imperfectly- 

 formed tubercles. 



The figures show at a glance the practical identity in these 

 respects between the two supposed New Zealand species, (" P. 

 Icdandii," figs. 1 and 2 ; P. edicardsii, figs. 5 and 6,) and the 

 marked difference of both from the true P. Icdandii, (figs. 3 

 and 4,) from the Cape. 



The carapace in the South African specimens is usually 

 broader in proportion to its length than in New Zealand 



