NO. 7 DAWSON : ALGAE OF THE GULF OF CALIFORNIA 119 



California a great number of a single species of Lithothamnium Were 

 secured from between 53 and 75 fathoms. Besides the corallines, one 

 species of Schizymenia was brought up from a 55-76 fathom haul off Isla 

 Partida in the upper Gulf. This record is surprising in view of the fact 

 that abundant phytoplankton through most of the upper Gulf greatly 

 diminishes the penetration of light to these depths. 



Entirely aside from the preceding considerations, two algal discoveries 

 merit particular mention here. Two species of brown algae turned up 

 most unexpectedly and serve veiy well to initiate a consideration of distri- 

 butional problems in the Gulf. One, Zanardinia, is a member of the 

 Cutleriales. Zanardinia prototypus (Nardo) Nardo (commonly known 

 as Zanardinia collaris (Ag.) Crouan) is the single species of the Medi- 

 terranean genus which has had, until the present, no unquestionable 

 records of a distribution far outside that general region. Beautifully 

 fringed, actively growing specimens, which were collected in several 

 localities from Turner's Island north, show exceedingly close resemblance 

 to the Mediterranean species and may prove to be identical. The species in 

 the Gulf is probably ephemeral, with a short period of vegetative growth 

 during the cooler seasons. It was found nowhere during the summer. 



The other very peculiar species is an IshigCj one which is at present 

 best referred to Ishige foliacea Okam. This has been known until now to 

 have a purely eastern Asiatic distribution. The two forms, /. Okamurae 

 Yendo and /. foliacea Okam,, are very abundant along the coasts of China 

 and Japan but have not been recorded elsewhere, in so far as the author 

 knows. Reproductive stages are unknown in spite of the abundance of the 

 plant. The Gulf material also is quite sterile. The finding of this Japanese 

 element in the flora of the Gulf is somewhat less startling than the dis- 

 coveiy of Zanardinia but is nevertheless remarkable. It is plentiful on 

 most of the rocky reefs in the northern part of the Gulf, where it had 

 attained a size of about two inches in January. It was encountered in 

 July on Tiburon Island in greater luxuriance and thus would seem to be 

 long lived, quite unlike Zanardinia. Only the flattened form is present; 

 whereas in the far eastern habitat both the flat and cylindrical forms are 

 found in close association. This one form is, however, widespread in the 

 Gulf area and apparently of broad ecologic tolerance. 



Other species of similar interest and importance are being found from 

 time to time as the investigations proceed. These will receive appropriate 

 mention with the accounts which are to follow of various algal genera 

 and families as they occur in the Gulf of California. 



