I 54 H. B. TORREY. 



A. diegensis. — Of all the species, this is the most irregular. It 

 agrees in general, however, with A. octocarpa. The hydrocladia 

 taper distalward ; the first hydrotheca is small and more or less 

 irregular, with short mesial nematophore ; the mesial nemato- 

 phore is most prominent between the extremes of the hydro- 

 cladia ; and there is a slight lessening of the obliqueness ot 

 the hydrothecal openings distalward. Fig. 6 is from a single 

 hydrocladium. 



Zoological Laboratory, 



University of California, 

 November 30, 1909. 



