1 68 



preceding somite", which words no doubt imply that the difference of length was not great 

 in his specimens and in the beautiful photograph of a specimen fr m the Hawaiian Islands 

 (Rathbux, 1. c.) the spine of the 4''^ tergum appears more than half as long as that 

 of the 3'"''. The species, observed and photographed by the renowned americafi carcinologist, 

 belongs, however, certainly to the typical ensifer, because Miss Rathbun had the opportunity 

 of comparing her Hawaiian specimens with a fair-sized individual from the Caribbean Sea. 



For the rest our specimens apparently fully agree with the typical species. The larger 

 male from the Kei-islands measures 98 mm. from tip of rostrum to end of telson and has the 

 size indicated by Milne-Edwards : unfortunately Miss Rathbun did not mention the size of the 

 specimens that she had observed and the numbers, mentioned by Spence Bate, are again a 

 mistake (entire length 64 mm. (2,5 inch), length of carapace 21 mm., of rostrum 23 mm., of 

 pleon 43!). In the specimen from Stat. 38, the carapace of which is 16 mm. long, the rostrum 

 is broken off near the tip of the antennal scales, but in the other specimens the postrostral crest 

 and the rostrum are armed dorsally with 16 or 17 teeth, five of which stand on the carapace, 

 while the lower margin has 9 teeth ; in form and size these teeth resemble those of Hcteroc. 

 Sibogae. In the larger male from the Kei-islands the rostrum is slightly .shorter than the carapace, 

 in the other just as long and in the two young specimens from .Stat. 105 the carapace is distinctly 

 shorter than the rostrum; in the two adult males the apex is not or scarcely situated above the 

 level of the postrostral crest, but in the two young specimens from Sulu Island rather much. 



Excepting the differences described above, the abdomen agrees for the rest with that 

 of Heteroc. Sibogae: like in this species there are on the i^' tergum on each side two small 

 tubercles situated above one another and the telson is armed likewise with 4 pairs of dorso- 

 lateral spinules besides those at the tip; the relationship between these two species is also 

 proved by the fact that of these 4 pairs of spinules the 2'"' and 3''^' pair are in both farther 



th 



distant from one another than the i^' from the 2"'' or the 3"' from the 4 



As regards the two pairs of antennae and the legs, both species seem to agree with 

 one another, but the dactyli of the three posterior legs are a little shorter in proportion 

 to the propodi, measuring in the adult male not yet one-third of the penultimate joints. 

 So are in the larger male from Stat. 254 the propodi of the 3'''^ pair 9,2 mm. long, the dactyli 

 2,6 mm., in the younger male, like in the young specimens from Stat. 105, they measure just 

 one-third of the propodi; in Miss Rathbun's photograph of a specimen from Hawaii (I.e.) the 

 dactyli appear also distinctly shorter than one-third of the propodi. In the adult Heteroc. Sibogae, 

 however, the dactyli are constantly longer than one-third of these joints and in younger indivi- 

 duals measure even slightly more than two-hfths of the propodi. 



Table of Measurements in millimeters: 



Carapace . 



Rostrum . 



Formula 



N" I and 2 Stat. 105; X" 3 and 4 Stat. 254. 



4 

 22,5 

 22,5 



6 



I 7 



