520 MK. H. N. EIDLET ON THE 



Antennal scale and peduncle as long as eacli other, and slightly 

 longer than the antennular peduncle. Basal segment of antenna 

 furnished below with a strong sharp spine. 



First pair of legs very unequal in size. Dactylus of larger 

 hand closing vertically, its greatest length being more than half 

 the length of the superior margin of the mauus ; without acces- 

 sory teeth. 



Anterior margin of the thumb on the inner side nearly 

 vertical, meeting the inclined superior margin at an obtuse 

 angle ; less than half the length of the superior margiu. Thumb 

 on the outer side without a vertical anterior margin, the superior 

 margin meeting the inferior at an acute angle and forming the 

 tooth. 



Manus smooth, without constrictions or depressions, longer 

 than the carapace; superior and inferior margins nearly parallel. 

 Carpus rounded above, not bearing a tooth. Meros three-sided, 

 flattened below ; superior margin produced in front into a blunt 

 process. 



Smaller manus simple ; dactylus and thumb approximately 

 equal in length to each other and to the manus. 



Carpus furnished above on the iuner side with a small pro- 

 jection. Meros resembling meros of larger limb, except that the 

 front process is smaller. 



In second pair of limbs the carpal segments are 1, 2 and 5, 3 

 and 4. 



First segment almost as long as the second, third, and fourth 

 together. Second segment a little shorter than the third and 

 fourth together, these being approximately equal ; fifth as long 

 as the second. 



Meros and carpus of third and fourth pairs of legs not spined. 

 Dactyli of limbs not bifid. 



One specimen. If I am right in referring this species to 

 Ah panamensis of Kingsley, with the description of which it 

 agrees well, it is of interest to note that it occurs upon the 

 eastern and western coasts of America. Mr. Kingsley described 

 his specimens from Panama and Acajutla. 



Alpheus obeso-manus, Dana. 



1852. Alpheus obesomanus, Dana, U.S. ExpL Exped., Crustacea, i. 

 p. 547, pb x.xxiv. fig. 7- 



Carapace smooth, furnished in front with a short rostrum. 



