NO. 1659. AMERICAN BPECIES OF ^YNALPHEVfl—COUTIERE. 59 



The lariic cliela has as its proportions, fino-ers 1 : total lenjjth 3.5 

 to 3.6; height about 1.3; the rehitive total h'ii<;th is a littk> less in the 

 female, but the dift'erence in size is very sli<>-ht; the form of the 

 chela is quite different from tliat of jS. longlcurpuH; the margins of 

 the palm are nearly parallel, the anterior margin terminating in a 

 strong tubercle which is prolonged by a point inclined downward; 

 i\\Q carpus is inserted in the prolongation of the greater axis; 

 the meropodite is proportionately stouter (proportion 2.05), its su- 

 perior margin terminating in a prominent, not spinous, lobe. 



The small chela has the following relative dimensions: Fingers 1; 

 total length 2.8 ; height 0.9G to 1 ; the movable finger terminates in 

 two short teeth ; the carpus is always much shorter than in S. longi- 

 carpas; in the largest examples its length does not surpass 0.43 of 

 the small chela, this proportion reaching 0.74 in the preceding species; 

 in the young this proportion remains the same, while it is very varia- 

 ble in S. longicarpus,' the carpus is alwaj^s a little less thick than the 

 palm, the margins of which are not parallel, as in S. longicarpus; 

 the meropodite is a little more than 3 times as long as wide, I have 

 found no sexual dijfferences. 



In the second pair, the first segment of the carpus, the sum of the 

 four following and the terminal chela are all very nearly equal; the 

 carpus is at least 7 times as long as wide. 



The third pair has these proportions in the male : Meropodite 2.2 ; 

 carpus 1 ; propodite 1.5 to 1.6 ; the meropodite is 3 to 3.2 times as 

 long as wide; in the female these proportions become, respectively, 

 2.6 ; 1 ; 2 ; and the meropodite is nearly 3.5 times as long as wide, the 

 entire appendage being more slender; the dactyl is short, very like 

 that of S. longicarpus. 



The second abdominal pleuron is not spinous in the male. 



The telson has its wide base contained 1.24 times, and its small base 

 about 4 times, in its height ; the spines of the dorsal surface, especially 

 in the male, are much stronger than those of the posterior border, the 

 inner of which, a little the longer, include between them 4 plumose 

 hairs and 2 groups of 3 simple hairs. 



The uropods bear upon the outer border 8 teeth in the female and 

 from 9 to 17 teeth in the male, the first and strongest of which pro- 

 longs the transverse suture ; and there is also a movable spine placed 

 between the two first teeth. 



As in S. longicarpus^ the eggs give rise to zoeae. 



The two species, which are very close to each other, are further 

 connected through the forms which represent them on the Pacific 

 coast. The Paris Museum possesses some specimens collected by M. 

 Diguet in the Gulf of California, which are distinguished from S. 

 goodei by the total absence of an antennal scale and by the presence 

 of 5 to 9 teeth on the external uropod even in the male, characters 



