DISTRIBUTION OF CERTAIN INVERTEBRATES ON A RESTRICTED 

 AREA OF SEA BOTTOM* 



Edna M. Perry, 

 Bellingham, Wash. 



The following table shows the distribution of the common Arthropods, 

 Echinoderms, and Mollusks on the area northeast of Brown Island, shown 

 by oblique rulings on the map on page 174. of the preceding paper.** The 

 distribution as given is for the month of July, 1915, and for the area in 

 question only. The species are arranged according to their uppermost 

 limit. Relative abundance and habitat are indicated by figures and letters : 

 — 1, abundant; 2, common; 3, few; 4, incidental or accidental; r, on rocks; 

 u, under rocks ; s, sand ; I, algae ; m, rock beds. 



Shore 



Lami- 

 narian 



Coralline 



Subcoralline 



Depth in Meters 



♦Editor's Note — The responsibility for the accuracy of this work is accepted 

 by Dr. V. E. Shelford of the Tliiiversity of Illinois, under whose direction the 

 work was done. Acknowledgments are due Prof. Trevor Kincaid, Miss Bertha 

 Challis, Dr. Nathan Fasten, Mr. H. M. Du Bois and Dr. H. D. Clark (Mus. Comp. 

 Zoology) for assistance in the preparation of the manuscript and reading the 

 proof. 



♦♦Shelford, V. E. Physiological Differences between Marine Animals from 

 Different Depths. Puget Sound Marine Sta. Pub. 1:157-174. 1916. 



(175) 



