1897.] NEAV YORK ACADEMY OF SCIENCES. 153 



favorable to deposition, however, a fair extent of beach has been 

 raised, giving an exposure, during extreme low tide of from fifty 

 to one hundred feet or more of till, mud or sand flats. But even here 

 the beach soon gives place seaward to deep water. Elsewhere 

 the littoral zone is represented by acres of eel-grass meadow, 

 sometimes covered by silt. This is notably the case at the head 

 of" Scow Ba^-," a shallow and nearly land-locked inlet communi- 

 cating with the east shore of Port Townsend Bay. In describ- 

 ing the fauna of the various littoral areas treated in the follow- 

 ing, we will commence at the most westerly point reached by the 

 shore collecting parties and follow the shore eastward, entering 

 all bays and inlets in which the fauna is worthy of remark. 



An interesting and regular fluctuation occurs in the tides giving 

 alternatel}^ what is locally known as the " long run " and the " short 

 run." In the former the water recedes very much farther than 

 in the latter, which subdivides the beach into a larger and sea- 

 ward area exposed once every twenty-four hours, and a narrow 

 border just below high-water line left bare twice as often. This 

 border, in general, proved a less favorable collecting field than 

 the more seaward area, though few careful notes were made upon 

 faunal diff'erences in these two subdivisions. 



The Beach Fauna. 



Sequim or Washington Bay is an inlet from the straits of 

 Juan de Fuca, situated about ten miles west of Port Townsend, 

 and exclusive of the areas around Cape Flattery and Neah Ba}^, 

 was the most westerly ])oint reached in shore collecting. A very 

 common form in the clam-shell detritus that covers the east 

 shore of Sequim Bay is an uudetermined species of Terehella, 

 which is almost always accompanied by a commensal Polynoid. 

 This commensal worm is without doubt distinct from the 

 Lepidametria found by Webster * accompanying the Amphi- 

 trite of the Virginia coast. A crab (Pseudograjjsus) is abun- 

 dantly represented here by individuals of various sizes and color 

 patterns. Some individuals are entirely white, others have white 

 carapaces or white legs, but the majority are ornamented by 

 scattered spots that follow gastric or hepatic areas of the cara- 

 pace. Although a series could be arranged, the white variations 

 are decidedly promiscuous, and. possibly, where these crabs 

 abound in colonies of various sized individuals, a more perfect 

 harmonization with the shelly beach is produced by indefinite, 

 than bj' definite markings. Saxidomus squalidus? is also abun- 

 dant here. 



* Annel. Chetop. of Virginia Coast, Trans. Alb Inst., Vol. IX. 1879 



