BIOLOGICAL SURVEY OF WOODS HOLE AND VICINITY. 123 



Northern types taken only at Crab Ledge. 



Animotrypane fimbriata Gulf of Maine to Vineyard Sound. 



Amphitrite cirrata Northern Europe to Crab Ledge. 



Cha^tinopoma greenlandica Northern seas, south in deep water to Massachusetts. 



Eunoe oerstedi Greenland to Vineyard Sound. 



Filograna implexa North Atlantic, south to Nantucket; off SankatyHead. 



Glycera capitata Northern Europe to Crab Ledge. 



Nothria conchylegia North Atlantic, south to Cape Cod. 



Myxicola steenstrupii North Atlantic, south to Massachusetts. 



Thelepus cincinnatus North Atlantic, south to Massachusetts. 



The low temperature of the bottom waters at Crab Ledge was considered on p. 5 1 

 and has been referred to elsewhere in our discussions of distribution. 



Attention has already been called to the fact that a number of our charted species 

 of annelids are recorded primarily from the inshore (adlittoral) stations, both in the Bay 

 and in the Soimd. This is true of Pisia palmata, Pisia intermedia, Parasabella microph- 

 thalmia, and in a lesser degree of Platyncrcis megalops. The same phenomenon is 

 exhibited by certain less common species, such as Sthenelais picta and Dodecaceria coralii. 

 All of these species were recorded wholly or chiefly from the Phalarope and Blue Wing 

 stations. 



On the other hand, certain species appear at first sight to show a tendency exactly 

 the opposite of that manifested by those just mentioned. These others were encoun- 

 tered with considerable frequency during the Fish Hawk dredging, but were seldom 

 taken by the Phalarope. Examples of such species are Eulalia annulata, Nephihys 

 bucera, Ninoe nigripes, Arabella opalina, and Rhynchobolus americanus. As a matter 

 of fact, however, the last two species, at least, are known to be common along shore, 

 where they may be dug up with the spade. Their absence from the Phalarope records 

 is very probably due to the failure of the dredges employed on the latter vessel to cut 

 deeply enough into the bottom. Indeed, it is quite possible that this same explana- 

 tion will hold for most of the cases in which species of Annulata seem to be restricted 

 to the Fish Hawk stations. 



And, in general, when we are considering any case in which a given species has 

 been obtained almost exclusively by one or the other vessel, the question must be asked 

 whether the personal element may not have played a part in determining this result. 

 It has been stated that the Fish Hawk and Phalarope dredgings were under the super- 

 vision of different persons. As is well known, different observers see different things, 

 depending upon what has especially been brought to their notice. We do not believe 

 however, that much importance need be attached to this source of error in considering 

 most of the species which have been listed here. In the case of certain of those which 

 have been mentioned as having a predominantly adlittoral habitat (e. g., Pista inter- 

 media), it is noteworthy that even the Fish Hawk stations at which they were taken 

 were mainly near shore. 



A considerable number of the Annulata, the names of which appear in our faunal 

 catalogue, are strictly intertidal in their habitat, or at least are confined to the shallow 

 waters just below the tidal limits. Such forms have naturally not been taken with the 

 dredge, although many of them are common enough in their proper habitat. Examples 

 of species such as these are Podarke obscura, Nereis limbata, Scoloplos jragilis, Amphi- 

 trite ornata, Notomastus luridus, Aretiicola crisiata, Arenicola marina, .^pirorbis spirorbis. 



