Mr. E. J. Miers on Malaysian Crustacea. 459 



Gonodactylus scyllarus (Linn.) . 



Amboina (an adult male), Goram (an adult male), New 

 Guinea (a male), Lette Island (a female?). 



The specimens from New Guinea and Lette Island approach 

 G. Bleekeri, A. Milne-Edwards, in having the median dorsal 

 carina of the terminal postabdominal segment more elevated 

 and acute ; but the rostrum, although acute, is not more pro- 

 duced at its distal end than in the typical G. scyllarus. 



Gonodactylus chiragra (Fabr.). 



Java, Karangbollong (an adult female), New Guinea (an 

 adult male), Amboina (a small male), Celebes, Macassar (an 

 adult female). 



The largest specimen (that from New Guinea) measures 

 fully 4 inches from the tip of the rostrum to the terminal 

 segment. The dilatation at the proximal end of the dactylus 

 is of a pinkish tinge shading into blue ; the distal end of the 

 dactylus is always more or less inflexed. 



Gonodactylus graphurus, White. 



Amboina (an adult male). A male of small size is in the 

 collection without special locality, in which, however, the 

 genital appendages are perfectly developed. 



on the under surface ; the third legs, in place of this spine, are armed 

 with a straight and slender styliform appendage, which reaches to the 

 middle of the merus joint, and is furnished at its distal end with a spear- 

 like head, which is acute in front, laterally dilated and produced poste- 

 riorly ; the merus joint of the fourth legs is dilated, carinated, and armed 

 with a strong tooth in the middle of its inferior margin. This joint in 

 the fifth legs, which are slender and much elongated, is less dilated, but 

 distinctly toothed (see the figures). In the female, the third legs are 

 armed only with a small spine. Length of the single male about 

 4]- inches. 



Hab. Yokohama, Japan (H. Batson Joyner, Esq.). 



Several specimens are in the collection. 



I have much pleasure in associating this species with the name of its 

 discoverer, who presented it, with several other interesting forms, to the 

 British Museum. The peculiarity in the .structure of the third to filth 

 ambulatory legs in the male, and particularly the remarkable appendages 

 to the basis joints of the second legs (which, it may be presumed, serve 

 as claspers during the act of coition), distinguish it from its congeners ; 

 but both sexes are further distinguishable by the form and dentition of 

 the rostrum, and of the laterally unarmed terminal segment. It is allied 

 to P. avirosbris, Dana, and P. Mastersii, Haswell ; but in the former 

 species the rostrum is much more strongly carinated above, and in the 

 latter the terminal segment is not acuminate ; both, moreover, have 

 a distinct dorsal carina on the carapace. 



