1911.] NATURAL SCIENCES OF PHILADELPHIA. 243 



gray mud; 4,475, same locality, 85-142 fathoms, .soft green mud; 

 4,4S0, Monterey Bay, off Santa Cruz Lighthouse, 53-76 fathoms, dark 

 green mud and sand; 4,485, same locality, 39-108 fathoms, soft green 

 mud and sand; 4,510, Monterey Bay, off Point Pinos Lighthouse, 

 91-184 fathoms, gray mud; 4,522, same locality, 130-149 fathoms, 

 gray sand and shells; 4,523, same locality, 75-10S fathoms, soft dark 

 mud; 4,552, same locality, 66-73 fathoms, green mud and rocks; 

 4,553, same locality, 65-74 fathoms, rock. 



NEPHTHYDIDiE. 

 Nephthys caeca (Fabricius) Oersted. 



Nephthys cceca, Ehlers, Die Borstenwurmer, 1869, pp. 588-617, Taf. XXIII, 

 figs. 10-34; Wiren, Vega Expeditionens, II, pp. 392-397, Taf. 30 and 31. 



After puzzling a long time over the many specimens of Nepthhys in 

 this collection, I have been unable to come to any satisfactory conclu- 

 sion regarding the number of species actually represented, and have, 

 therefore, tentatively begged the question and followed Wiren in 

 listing all of the forms represented under the above name. As a 

 matter of fact, scarcely a single specimen can be confidently said to be 

 typical N. cceca, though a number differ from it only intangibly. 

 Most of them, in having the neuropodial postsetal lip much larger 

 than the corresponding part of the notopodium, resemble N. hombergi 

 Aud. and M. E. (= N. assimilis Oersted, Malmgr en). Here belong 

 especially those from stations 4,443, 4,462, 4,482, 4,485, 4,510, 4,523 

 and 4,548, all in Monterey Bay. One lot (station 4,436), in the almost 

 total absence of parapodial lamella?, approaches very closely N. ciliata 

 (Muller) Rathke and has the rami widely separated as in N. incisa 

 Malmgren but all of them have more segments than the latter. 

 Specimens from stations 4,306 and 4,549 also approach this type, but 

 the lamellae are better developed. Two small specimens (station 

 4,482) have the long setse and long involute gills of N. malmgreni Theel 

 ( = N. longisetosa Malmgren non Oersted). Examples from many of 

 the other stations present intermediate characters, and it is for this 

 reason that I do not here separate the forms as I have done previously, 

 though I am by no means convinced that more than one species may 

 not be represented. 



The specimens vary in size from little more than 1 mm. wide to 8 

 and 9 mm. wide, the largest invariably incomplete. Many of the 

 smaller ones show a conspicuous color pattern in the form of an irregular 

 brown or dusky spot on the prostomium and bars of the same color 

 across many of the anterior segments. 



