73 



dorsal notch is deeper and much more definite in this species, 

 owing partly to the greater elevation of the ridge below it. 



The shape of the outer occludent margin is also different, for 

 in this species the large angular lobe is much nearer the tip and 

 its distal edge slopes much more, so as to make a decided angle 

 with the small tip; the tubercle at the articulation of the dactyl 

 is also more prominent, with a deeper notch each side of it. In 

 both species the hand is hairy, especially the distal part of the hand, 

 but the hairs are more abundant in this species. As preserved. 

 the present species has a conspicuous violet or amethyst-colored 

 tip to the dactyl, the color occupying the part beyond the plunger 

 and continuing back on the dorsal margin to the articulation, the 

 rest of the dactyl being white; but in armillatiis the tip is ivory- 

 white, while both sides are orange-red, spotted with yellowish- 

 white. 



Alpheus armillatus Edw., or Crangon armillatus. Banded Snapfiin" 



C* 1 ' i 



Alpheus armillatus H. Milne-Edwards, op. cit., vol. ii, p. 354, 1837. 



Coutiere, op. cit., 1899, p. 129, fig. 117; op. cit., 1910, p. 485. 

 Alpheus lancirostris Rankin, Crust. Bermuda, Ann. N. Y. Acad. Sci., 



xii, p. 541, pi. xvii, fig. 5, 1900. 



Crangon armillatus Hay and Shore, op. cit., p. 386, pi. xxvii, fig. i, text- 

 cut 9, 1918. 



TEXT FIGURES 53, 6b. PLATE XX, FIGURE 4b (photo). PLATE XXI, 

 FIGURES 4, 4a (photo). PLATE XXVI, FIGURES i id (details), 2 

 var. (?). PLATE XXIII, FIGURE 4 (photo). PLATE XXVII, FIGURES 

 i is (details). By A. H. V. 



This species can be most readily distinguished from the others 

 that are closely allied by the form of the rostrum and front, and 

 when recently caught, by the transverse bands of white with which 

 its body is conspicuously marked. 



The rostrum, viewed from above, is narrow lanceolate in form, 

 with an acute tip, projecting beyond the ocular lobes ; back of the 

 tip it expands slightly, and then becomes very narrow; but its 

 posterior dorsal portion becomes triangular and wide. In a profile 

 view the middle narrow portion is concave above, and the tip is 

 usually slightly bent downward. On each side there is a deep 

 and wide sulcus, ending rather abruptly posteriorly, while it pro- 

 duces a distinct emargination of the front margin. The eyes are 

 convex and the orbital lobe is prominent in front, with a slight 



