90 CALIFORNIA ACADEMY OF SCIENCES. 



ovules retained in Claytonia. The character is a sHght 

 one, but is assisted somewhat by the habit. 



The annual Calandrinias are probably none of them 

 nativ^es of North America. All the forms of C. Alenziesii 

 appear to be represented by Chilian species; C. Brezueri 

 is inseparable, at least in our herbarium specimens, from 

 C. compressa Schrad., and C. maritima belongs to the 

 picta group, from some of which, in our herbarium, it is 

 distinguished with sufficient difficulty. It often shows 

 the replum-like threads separating from the margins of 

 the valves so characteristic of Tal/iuiin parz'ifolinni. 



If Taliiinin hiiinilc had been known to Fenzl his 

 opinion of the relationship of Portulacacea? to Ficoidea^ 

 would have been materially strengthened. T. himiile 

 has a 3-celled and loculicidally dehiscent capsule, re- 

 minding of Mollugo. The septa are however very thin 

 and traces of similar structure in the form of central 

 vertical folds on the valves are to be found in various 

 species of Talinum, in Calandrinia maritima, Claytonia 

 Chaiiiissoiiis, JMoiitia foitana, etc. 



It is well known that seeds are viable before maturity. 

 This fact has a direct and important bearing upon the 

 accurate description of the embryo. In examining a 

 great number of seeds of the same species in this order, 

 the principal variation was found to be in the length of 

 the cotyledons. In those which had evidently reached 

 a sufficient age to germinate, the embryo ranged ac- 

 cording to degree of maturity, from sickle-shaped to a 

 nearly complete circle, and even, in some, the tips of 

 the cotyledons were hooked. In seeds having foliaceous 

 cotyledons the difference between the embryos viable 

 but immature, and mature seeds, is much greater. Bot- 

 anists who describe the embrvo from germinating seeds 

 only, are therefore liable to be much misled. 



