1895.] Entomology. 767 
I am glad to have an opportunity of describing this species, since 
Prof. Townsend had already named it in connection with the galls.— 
T. D. A. CocKERELL, N. M. Agr. Exp. Sta. 
Mexican Jumping Beans.—Occasionally one sees what are 
known as Mexican Jumping Beans, or Broncho Beans, exposed for sale 
in curiosity stores, or displayed as objects of interest in drug-stores, or 
other merchantile establishments. They are usually shown upon some 
smooth surface, as glass, the face of a mirror, or on the bottom of a 
smooth box. These beans are able to execute short leaps forward, or 
even turn over by a side-wise movement. If a dozen are placed in a 
box, so active are they, that some will be in motion most of the time. 
They are interesting objects both to grown people and children. Child- 
ren will watch them by the hourand beamused. They appeal strongly 
to the sense of the marvelous in older people, who seek a cause for 
everything, as there is no apparent explanation of these erratic move- 
ments. All the risk of dispelling the charm that gives attractiveness 
to the mysterious, the following explanation of the phenomenon is 
given. 
a l- 
These animated curiosities are the product of the plant belonging to 
the Spurge Family (Euphorbiaceæ) known to botanists as Sebastiania 
bilocularis. To this same family belongs the Castor Oil Bean. There- 
fore it would not seem inappropriate to apply the name bean to these 
saltatorial seeds, though they bear no resemblance in shape to beans 
belonging to the Pulse Family. 
The pods of plants belonging to the Spurge family are usually three 
lobed, as shown in cut C, and when ripe split up into three triangular 
valves with a roundediback as shown in cuts a, dorsal view, b face view, 
and e cross section.’ Each valve contains a single seed. It is to this 
tripartite form of the pod that the name Jumping Bean is applied. The 
plant they are obtained from has quite a wide geographical range, but 
the saltatorial seeds are found only in a limited area in Sonora, Mexico. 
Some of the seeds do not possess jumping powers and the active ones 
have to be selected. They are gathered by boys and find ready sale to 
travelers and dealers in curiosities. These diminutive “ Bronchos ” are 
