300 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 17 



dentations, some of which in middle and lower parts develop into simple, 

 pinnate, proliferous bladelets mostly 1-3 cm. long and with slender, stalk- 

 like bases; thickness of mature thallus about 280-400 /a; cortex of 2-3 

 layers of very small cells 4-7 /x in diameter; tetrasporangia not seen in 

 the Mexican material, but in Gardner 3039, scattered through the some- 

 what nemathecially modified cortex, about 30 fi long; cystocarps 

 scattered over the thallus surface, 1-2 mm. in diameter, not rostrate; 

 antheridia borne in a ±: continuous superficial layer without special 

 cortical modification. 



Type: Holotype is a cystocarpic specimen collected by W. A. 

 Setchell, no. 1313, Apr, 6-7, 1896, on sheet 92762 in the Herbarium of 

 the University of California, Berkeley. An isotype showing attachment 

 to the host is in HAHF. 



Type locality: On the stipe of Laminaria sinclairiij Duxbury 

 Reef, Marin County, California. 



Mexican distribution: Pacific Baja Calif. — D. 8646, d, drift, 

 Socorro, Dec; D. 9647a, drift, Punta San Quintin, Apr.; D. 8911, ?, 

 drift, Punta Baja, Jan. 



Pinnately proliferous examples of other coarse species of CallophyUis 

 are commonly incorrectly identified with C. pinnata. This species is 

 characterized by its distinctly dichotomous primary branching in which 

 the upper segments are quite long and ligulate ; the pinnate bladelets are 

 of secondary origin from tiny marginal dentae and are not the result of 

 regeneration following injury. The illustration of the type shows the 

 characteristic branching. The very large, sparse cystocarps, however, do 

 not seem to be characteristic. 



Smith's illustration (1944) does not correspond well with the type 

 and may represent a marginally proliferous example of another species, 

 although typical C. pinnata occurs in the Monterey area as represented 

 by Gardner 3039 from Pebble Beach, Carmel Bay (in Herb. U.C.). 

 Another Gardner specimen, 1812a, Dec, 1906 from San Pedro (in Herb. 

 U.C.) has been examined. It is identical in form and branching with the 

 technical type. 



The specimens figured by Dawson (1945c) are probably C. pinnata, 

 but are rather poor, damaged examples and should not be considered 

 characteristic. 



The Oregon examples of CallophyUis which appear to correspond 

 with Doty's interpretation of C. pinnata (1947, p. 175) are more 

 flabellate than the type, have terminal segments with a more corymbose 

 outline, and seem to represent a separate species. 



