14 DR. "W. T. CALM AN ON NEW OR RARE 



]). 81), fig. 52) figures the male of a '• Bodotria " having a single tooth on the dorsal 

 crest. It may possibly have been a species allied to the present. 



Occurrence. — Gulf of Siam, " Koh Kam, 5-10 fathoms. Th. Mortensen Coll." 

 Several specimens. Copenhagen Museum. Co-types in British Museum. Two young 

 and imperfect specimens of this species were obtained by Prof. Herdman in Ceylon, 

 and were recorded as " Cyclaspis sp." in my Report on his collections (Rep. Ceylon 

 Pearl Fisheries, Royal Society, pt. ii. 1904, p. 160). 



Cycl.\spis unicornis, sp. n. (Plate V. figs. 9-11.) 



I)escri])fion of wwiafure Female. — Total length 32 mm. 



The carapace is about one-third of the total length. The dorsal edge keeled, slightly 

 arched as seen from the side, and armed about a third of its length from the anterior 

 end with a sharp forwardly curved tooth. Pseudorostrum slightly prominent, the 

 ocular lobe reaching quite to the tip. Antennal notch wide ; antennal tooth acute, 

 not reaching quite as far forward as the tip of the pseudorostrum. The side of the 

 carapace is rough with small granules. 



The first leg-bearing somite is hidden, the second has a slight dorsal crest. 



The abdomen is a little longer than the ceidialothoracic region. The somites are 

 subcylindrical, with lateral articular processes. 



The first legs extend beyond the tip of the pseudorostrum in the natural position 

 for less than one-third of the length of the carapace. The basis is about three-fourths 

 of the lengtli of the distal segments together. The ischium and merus are very stout, 

 the former with the inner edge serrated. The three distal segments ai-e very 

 slender ; the carpus and propodus of equal length, and each about one-half longer than 

 the dactylus. 



The peduncle of the uropods is longer by about one-quai'ter than the last somite 

 and has its inner edge firtely serrated. The endopod is about two-thirds the length 

 of the peduncle, serrated on the inner edge, with a slender apical spine and four 

 spinules on the inner edge. The exopod is a very little longer tlian the endopod, has 

 a slender apical spine with a small spinule at its base and another a little way down on 

 the inner side. 



EemarJcs. — In the possession of a single dorsal tooth on the carapace this species 

 resembles the last, but it diff"ers in the absence of the lateral ridge on the carapace and 

 in many other characters. There is also a certain general resemblance to Stephanomma 

 qoesii Sars. It is stated, indeed, by Sars that in that species the lateral lobes of the 

 pseudorostrum are absent and there is no " frontal fissure " ; but I am inclined to 

 suspect that Sars has been misled by the ocular lobe reaching quite to the tip of the 

 pseudorostrum, and that Stephanomma will be found not to difi'er generically from some 

 of the species at present referred to Cyclaspis. 



Occurrence. — "Cruz Bay, St. Jan" (Danish West Indies). One specimen. Copen- 

 hagen Museum. 



