200 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



knowledge, been collected on the Pacific Coast north of 

 Monterey Bay. It appears to be exceedingly delicate, espe- 

 cially those parts of the frond which bear fruit. When 

 examining an herbarium specimen, the method of soaking 

 the desired portion in water, as pursued with P. perfo?-ata 

 and others, is entirely inadequate, water causing the almost 

 instantaneous dissolution of the jelly. It becomes there- 

 fore necessary to use a concentrated solution of corrosive 

 sublimate. 



P. leucosticta is fairly constant in shape, irrespective of 

 size, varying from oval in the young plants to oblong in the 

 older ones. It is but seldom laciniate, and the margin is but 

 slightly undulate. The base is decidedly stipitate, some- 

 thing in which the western specimen differs from the east- 

 ern and European plants, which are at the most substipi- 

 tate. Another difference between eastern and European 

 specimens of P. leucosticta on the one hand, and the west- 

 ern plants on the other, lies in the color, which in the latter 

 varies from cerise to dull brown, while the former appear 

 much lighter in color. 



This plant is, in the vegetative portion of the frond, con- 

 stantly monostromatic. No indications of a distromatic 

 nature have ever been found. 



The fronds are monoecious. At first the fruit is found 

 only at the tip and along the margins. In a ripe frond we 

 find a colorless margin, consisting of antheridia, together 

 with an empty network formed by the jelly-walls of those 

 sporocarps and antheridia which have discharged their con- 

 tents. Inside this margin, the sporocarps and antherida are 

 intermixed, the antheridia usually forming irregular, elon- 

 gated, colorless patches among the dark cerise sporocarps. 



The thickness of the reproductive portion of the frond 

 does not differ materially from that of the vegetative por- 

 tion, measuring from 25-50/^. This is an additional reason 

 for ascribing the increase in thickness in the reproductive 

 portions of the fronds of other species of Po7-fhyra to the 

 swelling of the jelly, since in P. leucosticta Thur. there is 



