THe MICROSCOPE. 39 
tapering, obtusely pointed prolongation forming rather less than 
one-half of the entire hyaline process. The length is about a7 
inch; width ¢747. (Fig. 9.) 
The villi clothing the general surface are longest immediately 
around the hyaline extinal processes, thence becoming shorter as 
they recede from the bottle-shaped projections, only to gradually 
elongate as they approach the next process. (Fig. 10.) Their 
length varies about scj7 to zsi~ inch. The entire surface of 
the spherical grain is villous, with the exception of the hyaline pro- 
jections and the sub-hemispherical papillee, which are never hirsute 
in any of these particular pollens. The diameter is about 745 
inch. 
The sweet potato belongs to the Convolvulacee, but the sweet 
potato seems to be a rare bloomer; or may it be that the cultivators 
are unobservant? Do the farniers never see the flowers? At any 
rate I have had trouble to get a specimen. The country within a 
radius of ten miles from the city where I live, is scored with my 
bicycle tracks, few of them leading anywhere except to sweet potato 
patches. In the search, I have had some of the most laughable 
experiences ; indeed, it must have been rather surprising to the 
unobserving truckman to see a fellowin a Jersey shirt and the short- 
est of short knickerbockers, come into a potato patch with a bicycle 
and gravely ask for sweet potato blossoms! The majority laughed 
in my face ; some became quite excited, affirming that sweet potatoes 
were never known to bloom ; others seemed anxious for their per- 
sonal safety only, getting away as if I were a visitant from another 
and a nether world. I found but three men and two women who 
treated the matter seriously, and from one of the women I obtained 
the sweet potato blossoms. In the search I met an intelligent florist, 
who has seen the bloom but once in twenty years, although he 
has cultivated the plant every season; while a man in his employ, 
although he has lived in a sweet potato region for fifty years, had 
never seen the plant in flower. Among the many whom I ques- 
tioned, only the five mentioned above had ever seen what I was 
seeking. 
IPOM@A PANDURATA, MEYER. (WILD POTATO VINE.) 
The pollen of this plant is no exception to that which we have 
already examined. The spherical grains are rather less than z}> 
inch in diameter. (+3'vv.) 
The extine gives origin to numerous hyaline processes, with 
their bases surrounded by villi projecting from the same membrane, 
