NO. 1659. AMERICAN SPECIES OF SYNALPHEUS—COUTIERE. 



45 



the anteniiiile, shorter than the carpocerite, which hist is a little de- 

 pressed, the proportion of its leng-th to its width being about 3.7; it 

 exceeds the antennule by half or even two-thirds of the distal article. 



The large chela is regularly ovoid; its measurements, taken along 

 the infero-external side, are: Fingers 1, total length 3.5; height 1.35; 

 there is on the supero-internal side, on the anterior margin of the 

 palm, near the articulation of the finger, a strong, sharp, and rather 

 slender spine. 



The small chela is in the proportion of about 2.7 to the preceding; 

 its relative dimensions are : Fingers 1 ; total length 2.25 ; height 0.8 ; 

 the fingers terminate in a simple point ; the carpus is short, scarcely a 

 fourth of the entire cheliped ; the meropodite is 2.5 times longer than 

 wide, its superior margin ter- 

 minated by a trihedral promi- 

 nence, not spinous. 



In the second pair the pro- 

 portion between the length and 

 Avidth of the carpus is about 0.5 ; 

 the meropodite is only 0.75 of 

 the length of the carpus. 



The proportions of the third 

 pair of feet are : Meropodite 

 2.2 ; carpus 1 ; propodite 1.6 to 

 1.7; the proportion between the 

 length and the width of the 

 meropodite is approximately 4, 

 often a little less; the dactyl is 

 a little curved, long, its hooks 

 are almost parallel, the dorsal 

 nearly twice as long as the 

 ventral. 



The length of the telson equals 1.06 times the Avidth at the base, 

 and 1.84 times its distal margin, which is regularly convex and bears 

 about tAventy plumose hairs and two pairs of feeble spines. 



The eggs are of small size (0.6 mm. in the nauplius stage, subse- 

 (^uently up to 1 mm.), and giA'e rise to zoeae. 



The length of the species does not exceed 25 mm. 



The typical specimens come from the region of the Bahamas and 

 Florida, but the species extends to the Bermudas and southward to 

 Brazil; some specimens from this last locality differ from the types 

 and may be separated as form hahiensis; the basicerite of the antennae 

 has its lateral spine very slender, its superior spine long and strong, 

 the lateral spine of the scaphocerite also slender, being as long as 

 the carpocerite; the small chela is more swollen than in the typical 

 specimens, the proportions being, fingers 1; total length 2.8; height 



Pig. 26. — Synalpheus minus bahiensis. a, 



FRONTAL AND ANTENNAL EEGION ; W , SMALL 

 CHELIPED OP FIRST PAIR ; m' , DACTYL OF 

 THIRD PAIR. 



