51 



both on the upper and on the lower side, measure two-thirds the length of the penultimate 

 joints. The 5"^ legs, finally, that are much thinner than all the preceding and nearly as long as 

 the legs of the y^ pair, reach with the two last joints beyond the scaphocerites ; their slender 

 dactyli are almost half as long as the slender, not broadened propodi, which are little shorter 

 than the carpal joints. 



In the male the coxae of the legs of the fifth pair are armed anteriorly with a sharp, 

 compressed tooth, that is slightly turned ontward ; in the female this tooth is smaller, more slender. 



The slender exopods of the i^' pair reach almost to the far end of the ischium, those 

 of the following legs appear gradually shorter. 



The two branches of the petasma are united anteriorly and terminale each at the distal 

 end in three lobules; the anterior lobules that are truncate, are armed along their distal margin 

 with minute spinules, a few partly larger spinules occur on the obtuse middle lobules and the 

 posterior lobules that are hooky and curved ontward, bear also a few sharp teeth ; the lobules 

 decrease in length from the anterior to the posterior. In young individuals, in which the 

 carapace, rostrum included, is 22 mm. long, the two branches of the petasma are already 

 united, but the small spinules are hardly developed. 



In the female one observes, immediately behind the coxae of the 4"' pair of legs, a 

 vertical trapezoid plate, the upper margin of which bears two small subacute teeth or tubercles 

 in the middle, while the outer angles are also dentiform; the submedian teeth are a little farther 

 distant from the outer angles than from one another, and the divergent lateral margins of the 

 plate are concave; between the legs of the 5''' pair the sternuni appears quadrangular, as broad 

 as long, with upstanding margins, of which the lateral are slightly concave; between the anterior 

 vertical plate and the quadrangular, horizontal, sternal plate are situated two small, oblong 

 tubercles. in the middle near one another; the posterior border of the quadrangular plate i. e. 

 the upper border of the posterior wall of the sternum, is notched in the median line and 

 emarginate at either side, presenting therefore two rounded lobes in the middle. The slightly 

 concave, lateral margins of the posterior wall of the sternum diverge backward, so that this 

 wall appears broader posteriorly than anteriorly. 



The branchial formula agrees with that given by Alcock (in : Catal. Indian Deep-Sea 

 Crust., Decapoda Macrura and Anomala, 1901, p. 20), but somite VIII bears perhaps an arthro- 

 branchia and a pleurobranchia instead of two arthrobranchiae and the VII* somite seems to 

 carry a quite rudimentary small gill, perhaps an arthrobranchia, as in So/. Koelbeli de Man. 



R e m a r k s. This Sol. Koelbeli from Japan seems to be the most closely related species, 

 it differs, however, from Sol. Melantho by the following characters. The cervical groove is not 

 interrupted by the post-rostral carina, the antennular peduncle reaches to the apex of the 

 antennal scales, the external maxillipeds extend only to the apex of the antennal scales, the 

 thoracic legs are shorter, so e. g. those of the 5"^ pair reach only with their dactyli beyond 

 the antennal scales, the mandibular palp has a somewhat different form and there are certainly 

 still more differences. 



Sol. disti?tcta (de Haan), which is most closely allied to the mediterranean Sol. sipho7iocera., 

 dififers at first sight by the existence of a spine at the antero-inferior angle of the carapace, 



SI 



