346 BOTANICAL GAZETTE [NOVEMBER 
has been so well pointed out by Jackson’ (1899) the most 
primitive form is to be expected. There was a small gall just 
at the base of the leaflet, and as it lay close to the midrib 
and partially deranged its tissues, the peculiar form of this 
leaflet may have been due to a pathological condition. 
Ill. ABNORMAL FLORAL ORGANS. 
In the summer of 1900 a small plot of Lathyrus odoratus L. 
was found to be producing a considerable number of abnormal 
flowers. A few of these were dissected and the parts carefully 
drawn at the time ( figs. g-30). The inflorescence of this species 
usually has only three flowers, but occasionally varies from two 
to four. /ig. 4 represents a double inflorescence in which a two- 
flowered inflorescence has apparently arisen, axillary to the 
lower flower of a four-flowered inflorescence. Abnormal floral 
organs were numerous and interesting. I have shown the parts 
and arrangement of the normal flower in jigs. 5-7. The combi- 
nation of abnormalities in each flower can best be exhibited by 
description of the cases examined. In each case the floral 
organs not mentioned were normal. 
Case z. An outgrowth from the margin of the sinus between 
the upper calyx teeth assumed the form and coloring of the 
vexillum. Vexillatwo. (Fig, 8.) 
Case 2, Calyx with a petaloid outgrowth from the upper 
sinus. This outgrowth had a lanceolate form instead of the 
nearly orbicular form of the vexillum. Vexilla two. Stamens 
eleven, all united. 
Case 3. The upper edge of an upper calyx lobe dilated 
slightly and colored. Vexilla two, the outer having a downward 
hook like that of an ala, and somewhat narrower than normal. 
Stamens eleven, two nearly free at the base but united to the, 
other nine above. (Fig. 9.) 
Case 4. Calyx the same as in 7. Vexilla two. Stamens 
twelve, all united to form a tube. 
5R. T. Jackson, Localized stages of development in plants and animals. Mem. 
Boston Soc. Nat. Hist. 5: 89-153. pls. 16-25. 
