24 



EXPLANATION OF PLATES. 



Plate I. Penaeus setiferous. "Lake Shrimp." Side view. 



Plate II. Penaeus setiferous. Dorsal view of a smaller indi- 

 vidual. 



Plate III. Penaeus setiferous. First and second pairs of 

 swimmerets, of the male and female. 



Plate IV. Figure 1 — Parapenaeus constrictus. 

 Figure 2 — Xiphopenaeus kroyeri. 

 Figture 3 — Sicyonia dorsalis. Twice natural size. 

 Plate V. Figure 1—Bithynis ohionis. Female with eggs. 



Figure 2 — Palaemon tenuicomis. Female with egg. 



Twice natural size. 

 Figure 3 — Palaemonetes carolinus. Female. Twice 

 natural size. 



Plate VI. Chloridella empusa. 



The figures of the entire animal are from photographs by the 

 author and are natural size, unless otherwise stated. 



