UNIVERSITY OF CALIFORNIA PUBLICATIONS 



IN 



BOTANY 



Vol. 7, No. 2, pp. 25-38, plates 5-6 October 4, 1916 



NOTES ON THE CALIFORNIAN SPECIES OF 



TBILLIUM L. 



II. THE NATURE AND OCCURRENCE OF UNDEVELOPED 



FLOWERS 



BY 

 THOMAS HAEPER GOODSPEED and EGBERT PERCY BRANDT 



In the first paper of this series (Goodspeed and Brandt, 1916) 

 reference was made to the fact that when one examines in the field 

 an assemblage apparently of any species of Trillium, a considerable 

 number of the plants npon superficial examination appear to contain 

 no floral parts within the whorl of leaves, but upon more careful 

 examination are found to be provided with more or less highly 

 differentiated floral primordia, making up what will be spoken of 

 throughout as "undeveloped" flowers. Plates 5 and 6 show various 

 types of these undeveloped flowers. Table 1, below, consists of 

 measurements of the length of the various structures found in a 

 number of undeveloped flowers of different stages of complexity, 

 the structures measured being named in some cases rather arbitrarily 

 and in general for convenience as though corresponding in position 

 to the distinct floral whorls that make up the normal flower of 

 Trillium. From a very large number of specimens examined we are 

 led to make the rather sweeping statement that every plant of T. 

 sessile var. giganteum H. & A. and T. ovatum Pursh., the two species 

 peculiar to Western ^Middle California, contains floral organs which 

 are either complete in number and differentiation, giving a normal 

 flower, or are reduced in number and differentiation to give various 

 types of undeveloped flowers. In addition, all the apparently flower- 

 less plants of T. sessile L. from Illinois and of T. grandifiorum 



