252 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 10 



Platynereis agassizi (Ehlers) 



Nereis agassizi Johnson, 1901, pp. 399-400, pi. 4. 



This is common throughout the Dillon Beach and Tomales areas, 

 usually associated with algae ; at Tomales Point, ocean side, it constructs 

 matted masses in narrow-leaved eel grass. Unlike most nereids, it is a 

 tube dweller, and sometimes harbors Halosydna brevisetosa Kinberg. 

 Length is 50 to 70 mm. 



Neanthes brandti (Malmgren) 



Hartman, 1938, p. 80; 1940, p. 219. 



At Tomales Bay, it is found in sand flats. Length is 200 to 500 mm. 



Neanthes lighti Hartman 



Hartman, 1938, pp. 80-81, figs. 1-4. 



At Stempell Creek, near the mouth, and in Tomales Bay, it occurs 

 in sandy flats. It occupies vertical burrows open at the surface. It was 

 found viviparous in June, 1941, by Miss Marian Pettibone. Length is 

 25 to 35 mm. 



Nereis vexillosa Grube 



Johnson, 1901, p. 399, pis. 3, 4. 



This is common at Second Sled Road, Perch Rock Point, and at 

 Tomales Point, ocean side, in mussel and barnacle beds. Length is 80 to 

 150 mm. 



Nereis procera Ehlers 



Johnson, 1901, pp. 400-401, pis. 4, 5. 



This occurs in mud flats of Tomales Bay. It is long, slender; color 

 in life is light red. Length is 100 to 140 mm. 



Nereis mediator Chamberlin 



Chamberlin, 1919, p. 11. 



This is common in algal holdfasts at Tomales Point, ocean side, and 

 in the vicinity of Dillon Beach. It is often bright green in life and when 

 preserved. Length is 50 to 70 mm. 



Nereis eakini Hartman 



Hartman, 1936, pp. 472-474, fig. 49. 



At Tomales Point, ocean side, it occurs among Bryozoa and sponge 

 masses. Length is 50 to 80 mm. 



