Hemi-Syncotyly, Syncotyly, Amphi-Syncotyly. 459 
cotyls and types in which the fusion has extended to the 
very tip. The lesser degrees of fusion are usually rarer 
than the greater, and, therefore, in order to get a fairly 
complete series of transitional forms, cultures from the 
seeds of selected individuals are required. It is often 
very difficult, especially in forms with stalked cotyledons, 
to distinguish between the lowest grades of fusion and 
pure dicotyls. If the crops are recorded before the 
cotyledons and their peduncles have grown to their full 
extent, it may easily happen that occasional seedlings, 
Fig. 90. Ocnothera glanca. Syncotylous seedlings. A and 
B, ordinary syncotyls ; C and D, pitcher-shaped syncotyls 
or amphi-syncotyls. 
which, after further growth, will prove to b hemi-syn- 
cotylous, are mistaken for dicotyls. 
The hemi-syncotyls constitute the minus variants of 
the series, the corresponding plus variants being the 
amphi-syncotyls of double or two-sided syncotyls (amphi- 
cotyls). In these latter cases the cotyledons are fused 
on both sides, often more on one side than the other, 
sometimes equally high on both sides. The cotyledons 
constitute a pitcher (Fig. 90 C and D, and Fig. 91) 
which is either cylindrical or urn-shaped or disc-shaped, 
