I 20 

 f 55. Sicyonia disptjwsa de Haan. 



Sicyonia bispinosa de Haan, Fauna Japonica. Crustacea, 1849, p. 195, Tab. XLV, Fig. 9. 



Stat. 99. June 28/29/30. 6°7'.5 N., 120° 26' E. Anchorage off North-Ubian, Sulu Archipelago. 

 I young male, taken at the surface. 



The identification of this specimen, that is very young, with Sic. bispijiosa is probably 

 also correct; it agrees fairly well with the description, but, as regards the figure, I wish to 

 remark that the rostrum appears in this specimen a little less broad in proportion to its 

 length. It is only 13,5 mm. long, whereas Sic. dispinosa attains a length nearly 3-times as 

 large. The rostrum that reaches to the far end of the 2°<^ article of the antennular peduncle, 

 and that is rather strongly ascending, is 2,2 mm. long, measuring two-fifths the rest of the 

 carapace and it is 6-times as long as wide. It appears to be 0,36 mm. broad as well 

 at the base as at the level of the 3"^ tooth, this tooth included, and both margins are therefore 

 parallel. The upper margin bears 5 rather small teeth that are all placed on the rostrum 

 itself; the 1^' tooth stands at the first fourth of the upper margin, the 2"<i is just as far distant 

 from the i^' as from the 3"^, the 4''^ is half as far distant from the 3''*^ as are the preceding 

 teeth from one another and it is situated close to the 5"^ near the pointed tip of the rostrum; 

 the 4''' and the 5''' are curved downward and this is still more the case with the pointed 

 extremity of the rostrum, which extremity is strongly curved, the tip being almost at a right 

 angle with the rostrum, so that the 5''^ tooth even projects beyond it. The tooth at the end 

 of the lower margin reaches not so far forward as the 4"^ tooth of the upper. The toothing of 

 the rostrum which is tridentate at the tip, therefore fully agrees with de Haan's description and 

 figure. The lateral crest that disappears just beyond the 2"<^ tooth, runs as far distant from the 

 upper as from the lower margin. Close to the straight lower margin three or four spiniform 

 setae are implanted, at either side, between the 2"*^ and the 3''^ tooth. 



There are two teeth ou the dorsal carina of the carapace, that are much larger 

 than the rostral teeth ; the tip of the anterior tooth is situated at one-fourth the length of the 

 carapace from its anterior margin and more than one and a half times as far distant from the 

 tip of the i^' rostral tooth as the latter from the tip of the 2"<i tooth, and little farther distant 

 from the tip of the i^' rostral tooth as from that of the posterior tooth of the carapace. The 

 tip of the posterior tooth is situated just behind the middle' of the carapace. 



Orbital angle subacute; hepatic spine of moderate size, its tip twice as far distant from 

 the orbital angle as the spine itself is long. 



The abdomen resembles that of Sic. parvida de Haan. 



The eye-peduncles hardly reach to the middle of the rostrum. As in Sic. parvti/a, the 

 antennular peduncle reaches with one-half of its terminal joint beyond the truncate tip of the 

 lamina of the antennal scales, but the peduncle has a more slender form: so e.g. the 

 2°^ joint appears in Sic. parvjila one and a half times, but in Sic. bispinosa twice as 

 long as wide, when viewed at from above. The spine at the far end of the outer margin 

 of the I ^' article is also more slender and the distance between its tip and that of the 

 stylocerite is just as long as the 2^^ article. 



120 



