a Cucurbitaceous Genus from Mexico. 11 
is divided into three double longitudinal lines bearing pollen; the 
latter is covered by a brittle tegument opening lengthwise. Flowers 
male and female. (On more than twenty occasions that I have been 
to the place where these plants grow, I have never met with a female 
flower : male flowers are very abundant at all seasons. I was already 
despairing of finding one, when last week I discovered several ripe 
fruits at the point of opening, five or six of which I took home for 
further examination. As yet, I have not been able to meet with a 
female fiower, but shall do all in my power to obtain one.) Fruit 
oval, pointed at the apex, and crowned by the scar of the calyx (or 
corolla?), covered with numerous spines from 1 to 2 inches long. 
Ovary adherent, solitary, four-celled ; ovules solitary, attached to a 
placentation formed by a column terminating in four claws like those 
of an animal, to each of which at its point an ovule is attached, one 
or two of which seldom arrive at maturity*. Seeds flat; testa horny; 
internal membrane thin, elastic, and veined; perisperm very abun- 
dant, bitter and purgative when raw, but having the taste of a walnut 
when cooked; embryo very small, flat ; cotyledons foliaceous, muci- 
laginous ; radicle straight, turned towards the hilum: the embryo- 
nary sac disappears in ripe seeds. 
“ Parts of the plant which are not exposed to the whole force of 
the sun ripen no fruit. From the fleshy part of the epicarp exudes 
a very transparent gum, clear as glass. ‘The mesocarp of the fruit 
is composed of a network of numerous fibres, of a white colour, 
crossing each other in all directions. The plant is only found in the 
mountains of Mactlactleahuatl, or in places contiguous to them. 
It flowers all the year round; but only towards the end of August 
and September ripe fruits are found. 
“The squirrels eat the kernels greedily ; but as the fruit is very 
spiny, they cannot attack it; however, being acquainted with its 
mode of opening, five or six of them are in waiting every morning, 
and as soon as a fruit bursts, hasten to devour the seeds. As soon 
as the rays of the sun reach a ripe fruit, it will open, but not before. 
The shock is so strong, that the fruit is severed from the stalk 
and thrown heavily to the ground, while the seeds are dispersed in 
different directions. 
** Most curious is the manner in which the fruit opens. Towards 
seven o'clock in the morning, on a sunny day, the fruit splits from 
a to b (fig. 3 of the accompanying drawing), then from @ to e, from 
e to d, from d to e; when the opening has attained the point e, the 
fruit turns the piece A completely round, forces the column com- 
posing the claws in a reclining position, at the same time throwing 
the seeds with great force several yards’ distance. The sections /f, 
cf, df, and ef open afterwards slowly. The first part of the pro- 
cess lasts about half a minute, and the latter one minute. 
* Hueo Fink.” 
** Hacienda San Francisco, near Cordova, 
Sept. 10, 1850,” 
* “ Since then, [ have remarked that in some fruit all the four ovules 
ripen; but generally one is abortive, as shown in fig. 20,—H. F.” 
