STATISTICAL BIOLOGICAL STUDY. 67 



moenas, Weldon, '93, Pearson, '94; various dimensions, Cran- 

 gon, Weldon, '90; length of rostrum, Palsemon serratus, 

 Thompson, '94, Pearson, '94; number of rostral teeth of 

 Pakemonetes, Weldon, '92 b , Pearson, '95, Duncker, '00. 



Lot. A, mm. a, mm. C,% 



Eupagurus, short edge of R. chela: 



$ deep water 9.708.085 2.76 28.5 



t shallow water 10.272.075 2.59 25.2 



? deep water 7.400.033 1.06 14.3 



5 shallow water 7.485.029 1.02 13.6 



Eupagurus, long edge of R. chela: 



t deep water 17. 97 .14 4.73 27.8 



* shallow water 18. 68+. 13 4.38 23.5 



9 deep water 14.14.06 1.67 11.9 



? shallow water 13.97.05 1.82 13.0 



Eupagurus, carapace length: 



$ deep water 8.59db.05 1.67 19.4 



t shallow water 7.54.03 0.94 12.5 



$ deep water 7. 12 .03 0.86 12.1 



PalsBmonetes vulgaris, dorsal spines . 8.28 0.81 9.83 



" " ventral spines. 2.98 0.45 15.03 



Palaemonetes, varians, dorsal spines . 4.31 0.86 20.00 



ventral spines. 1.70 0.48 28.26 



Amphipoda. Seriations of lengths of body, of second 

 antennae, and of ratio of second antennae to body-length, 

 Smallwood, '03. 

 Annelida. 



Chcetopoda. Teeth on jaws of Nereis virens. Right: A = 

 10.055.045, a= 1.339 . 032, C=13.3%; Left: A=10.00 

 .044, o= 1.306 .031, C=13.1%, Hefferan, '00. 

 Bracliiopoda. 



Seriation of widths breadth, width of sinus -f- depth, num- 

 ber of plications on ventral and dorsal valves in sinus and on 

 fold, Cummings and Mauck, '02. 

 Bryozoa. 



Number of spines on statoblasts of Pectinatella magnifica. 

 A = 13.782 .031, <r= 1.318 .022, C= 9.57 .16, Davenport, 

 '0CK 

 Mollusca. 



Gastropoda. Frequency polygons of ventricosity, weight, 

 and index of Littorina littorea for 3 British and 10 American 

 localities greater variability in America. Index: <7=2.3%, 



