176 



The numerous specimens from Stat. 314 resemble those from the Stations 38 and 45, 

 the rostrum being moderately recurved in the adult males, more strongly in the adult ova- 

 bearing females; in these adult specimens it is nearly as long as the carapace, or a little to 

 one-third longer, or, as in the adult ova-bearing female (N" 37) slightly shorter, in the younger 

 specimens one and a half to twice as long. 



The adult male (X" 47) from Stat. 316 differs from all the other specimens by the small 

 number of teeth on the rostrum and should be considered as an exception. The rostrum, a 

 little shorter than the carapace, is very little upturned, so that the ape.x is situated at the same 

 level as the carapace. There are but 7 teeth on the upper margin, besides a rudimentary tooth 

 in front of the foremost one; 3 teeth stand on the carapace, the 2"'^ twice as far from the 

 3rd as from the i^', while the 7''' is placed a little behind the tip of the antennal scale; lower 

 margin only with 6 teeth. In the much younger male (N° 48) also only 9 teeth are observed 

 both on the upper and the lower margin, the teeth are as far distant from one another as in 

 Bate's figure i 9, 'Jut the ro.strum is a little more upturned and, as usual, 3 teeth stand on 

 the carapace, the 2°*^ twice as far from the y^ as from the 1^'; it is one-fourth longer than 

 the carapace. In the females the rostrum is more strongly recurved than in the Challenger 

 type, in the largest female one-fourth longer than the carapace. 



We may conclude from the measurements of 53 specimens, which are indicated in the 

 Table, that in adult individuals of Ileteroc. dorsalis Bate the rostrum is nearly as long 

 as the carapace, either a little shorter or longer, or distinctly longer, to almost 

 one and a half as long as the carapace and that in younger specimens it appears 

 considerably longer, to even a little more than twice the length of the carapace. The 

 Table also teaches us, that the rostrum is usually armed dorsally with 12 — 14, ventrally with 

 II — 14 teeth, more rarely 10 or 11 teeth occur on the upper margin, and, as very rare 

 exceptions, 7 or 9 or 1 5 or 16 teeth were observed on the upper margin, 6 or 8 or 9 or 15 

 on the lower. The two females from off Banda Island, on which this species was founded 

 by Spence Bate, should therefore be regarded as such a rare e.xception, because the upper 

 margin was armed with 8 and the lower with 7 teeth. Usually three teeth stand on the 

 carapace, posterior to the orbital margin, about in 80 per cent of the specimens, more rarely 

 two antl in this case the 3''' tooth is often placed above the orbital margin: specimens, however, 

 in which, like in the Challenger types, the_3'''i tooth stands above the eyes, were 

 also obtained by the "Siboga". As a conspicuous and constant feature of this species the 

 four tubercles must be considered, which in a transverse row occur on the tergum 

 of i^' abdominal .somite. 



I am not quite sure, whether Ilctcroc. Alplionsi Bate, taken by the "Challenger" south 

 of the Philippines and off Japan, is a distinct species or not. According to the author of the 

 Report on the Challenger Macrura the rostrum should be one and three-fourths longer than 

 the carapace, but the measurements of the female and the male, mentioned b\- him on p. 633, 

 agree with those of Heteroc. dorsalis, the rostrum being only one-third or one-fourth longer 

 than the carapace — they show likewise the .same slip of the pen, for the entire indicated 

 length is only the length of the rostrum and the abdomen combined! In Bate's description 



