408 University of California Publications in Zoology [Vol.22 



Teredo beachi (ibid., p. 19). We feel compelled to state further that 

 during three years' intensive collecting in San Pablo Bay and the 

 vicinity of Mare Island and Carquinez Strait by Kofoid and the 

 writer, we have not seen any pallets which very closely approach 

 the type of beachi as figured (ibid., pi. 32, fig. 4), although this is 

 asserted by Bartsch (1921, p. 22) to be the form causing the extensive 

 damage in this region. We have likewise sought in vain for pallets 

 of the form in question in material collected from the Mare Island 

 dikes in 1914 by Barrows. We are forced to believe that the pallet 

 figured for this form has been either very badly drawn, or drawn 

 from an extremely aberrant specimen. Whatever be the original of 

 this figure, it is certainly not typical of anything occurring in the 

 San Francisco Bay region. 



It should be noted in this connection that the material identified 

 for Barrows by Bartsch as Teredo diegensis was taken from the type 

 locality of beachi, and hence could not have been townsendi, as 

 stated by Bartsch (1922, p. 27). The latter form occurs at only one 

 locality in San Francisco Bay, namely South San Francisco (Kofoid, 

 1921, p. 35), where Bartsch 's specimens were collected by Townsend, 

 who was for a time employed by the San Francisco Bay Marine Piling 

 Committee. It has never as yet been found in the brackish waters into 

 which T. naval is extends its range in San Francisco Bay. 



It would appear, then, that, unless their validity can be estab- 

 lished on other grounds than the form of the pallets, the proposed 

 species beachi, novangliae, morsei, and beaufortana are in a some- 

 what precarious position. The status of beachi as determined by the 

 shell we have treated in an earlier paper (1922, pp. 313 ff.). The 

 shell of novangliae is chiefly distinguished (Bartsch, 1922, p. 20) 

 by the size of the auricle and the roughness of the median area, char- 

 acters which we have shown (1922, pp. 309, 311) to be extremely 

 variable. The distinctive character of morsei (Bartsch, 1922, p. 22) 

 is "in having the ridges of the anterior area more numerous and 

 much more closely spaced"; these characters we have shown (1922, 

 pp. 306 ff.) to be matters of age and environment. Teredo beaufortana 

 we fear will have to await general recognition until its shells are 

 brought to light. 



There is no reason to believe that variation in Teredo navalis 

 is a phenomenon limited to San Francisco Bay. Bather is it a bio- 

 logical factor to be reckoned with wherever the distribution of this 

 species extends. Such being the case, we would urge extreme caution 



