46 



PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxvi. 



1 to 1.09; the proportion between the length and the width of the 

 meropodite is 2.1 instead of 2.5; the dactyls, in the third pair espe- 

 cially, have their two hooks almost equally strong and long. 



The strong superior spine of the basicerite, and also the greater' 

 thickness of the small chela, are found again, less marked, in some 

 specimens from the Bermudas and from Florida, which it would be 

 hardly advisable to separate as a distinct form. A specimen from 

 Sarasota Bay, Florida, has an abnormal small claw, approximating 

 the large one in its proportions; the fingers measure only one-third 

 of the total length, and the anterior border is spinous. This tendency 

 to the reestablishment of the symmetry of the two claws is not very 

 rare in the Alpheidw ; and, although leading to the same results, it is 



diametrically opposed to 

 the cases of hypotypic 

 regeneration, of which 

 also examples are known. 

 Other very interesting 

 specimens differ mark- 

 edly from the types by 

 the Avidth of the anten- 

 nal scale, only 7.3 times 

 longer than wide, recall- 

 ing by its form that of 

 S. hrevicarpus. Other 

 characters of the species 

 are in these specimens 

 weakened in the same 

 Avay; for example, the 

 carpocerite is a little less 

 Fig. 27.^ — synalpheus minus antillen.sis. «, frontal swollen, the proportion 



AND ANTENNAL REGION ; A', LARGE CHELA ; /.', SMALL j; '- , 1 j1 x -j. • Ij.^, 



CHELIPED OF FIRST PAIR; Vl', DACTYL OF THIRD I'AIR. ^^^ lenglU lO ItS WlCltn 



(3.7) declining to 4 in 

 the male; of the members of the second pair the carpus is 10 times 

 longer than wide. On the other hand, the dorsally strongly spinous 

 basicerite, the thick meropodite of the third pair, the telson widened 

 at its distal end, and the form of the chelae of the first pair, permit 

 the determination of these examj^les as S. minus. They indicate in 

 what way the variation giving rise to the species hrevicarpus is 

 accomplished. 



Among the other varieties of >S'. minus, it seems to me possible to 

 separate a form antillensis. The specimens which are referred to this 

 form come mainly from Porto Rico and St. Thomas. They differ 

 from the types in the frontal teeth, which are long and narrow, es- 

 pecially the rostrum, and in the antennule, which is only 4.2 to 4.3 



