34 THE NAUTILUS. 



impossible word into exacutus, or others did, is enough to show 

 that it was an error. The purpose of nomenclatural rules is to pre- 

 vent mistakes and misunderstandings ; the means, to adhere to the 

 original spelling, so far as consistent with sense. In the case of PI. 

 exacutus for exactions, there is no possibility of a mistake, and I, for 

 one, shall write exacutus after this. 



In Say's article there is under Cyrena : " Shell triagonally 

 rounded . . .,"- evidently an error ; it should be " trigonally." If 

 this were in a name it would be perpetuated like " exacuous." 



MOLLUSCAN FAUNA OF MONTEREY BAY, CALIFORNIA. 



BY S. S. BERRY. 



(Continued from p. 22.) 



Cylichna eximia Baird. 12 fathoms. 



Cylichna attonsa Carpenter. 28 fathoms ; one young specimen. 



Tethys (= Aplysia) californica Cooper (?). The common sea- 

 hare of Monterey Bay seems to differ somewhat from those of the 

 southern part of the state, and may prove to be distinct when a care- 

 ful anatomical examination has been made of both. The form ob- 

 tained is quite common along the shore. It is large and of a brown 

 color, irregularly blotched. 



Tethys (californica, var. ?). A small red form was dredged at 12 

 fathoms depth, which may or may not prove distinct from the shore 

 form. At any rate, it is very different in appearance. 



Archidoris montereyensis Cooper. 25 fathoms. Whether one 

 collects along the shore or dredges in the bay, the Nudibranchs 

 form one of the most striking and characteristic features of marine 

 life in the Monterey region. Neither individuals, nor species, nor 

 even genera, are few in number, as the following incomplete list will 

 show. For the identifications, Professor MacFarland's careful paper 

 on the Monterey Bay opisthobranchs (Bulletin of the Bureau of 

 Fisheries, Vol. XXV) is the best work, and was constantly used by 

 us as a text book in their study. It is beautifully illustrated, and 

 should be in the library of every Pacific coast student. 



Anisodoris nobilis MacFarland. Very common at low tide. 



Rostanga pulchra MacFarland. A few of these bright-red ani- 

 mals found at low tide. 



