EXPLANATION OF PLATE 37. 



Fig. 1. 

 Fig. 2. 

 Fig. 3. 

 Fig. 4. 

 Fig. 5. 

 Fig. c. 



Drill I>o\v. 



(Cat. N. G380i, U. S. N. M. Point Oope. Collected by E. W. Kelson. 



Drill Bow. 



(Cat. Ko. 4534C, U. S. N. M. Cape Nome. Collected by E. AY. Nel.soii.) 



Drill Bow. 



(Cat. No. 33191, U. S. N. M. Norton Sound. Collected by E. W. Nelson.) 



Drill Bow. 



(Cat. No. 89510, U. S. N. M. Poiut Barrow. Collected by Lieut. P. H. Kay. l'. S. A.) 



Drill Bow. 



(Cat. No. 5(i518, U. S. N. M. Point Barrow. Collected by Lieut. P. H. Ray, TJ. S. A.) 

 Drill Bow. Tiiis specimen is 24| iuclies long. 



(Gat. Kg. 24540, U. S. N. M. St. Michaels. Collected by L. M. Turner.) 



