V62 REPORT UNITED STATES GEOLOGICAL SURVEY. 



violent muscular action drew the whole stock of young and tender clover 

 toward him, and when all the substance was sucked out he let the plant 

 go and it (the stock) flew back to its former place. The leaf and stem 

 were entire, bat looked as though it had been boiled. I then laid a small 

 l)iece of cold mutton down, and he appeared to feast both on the fat and 

 lean, dragging them after him as his powers of suction could not act as 

 well as if they had been held like the clover-leaf. I also find that when 

 the male and female are together, they appear as one worm of double 

 the size." 



The earth-worm, like snails and slugs, is hermaphrodite. In Luni- 

 bricus agricola oi Europe, the female sexual apparatus consists of two- 

 ovaries lying in the thirteenth segment, and two oviducts (segmental 

 organs), which, beginning in a trumpet-shaped opening, collects several 

 eggs into a small sac, which is ejected through an opening on each side 

 of the ventral surface of the fourteenth segment. Moreover, we find in 

 the ninth and tenth segments two pairs of pyriforra seminal recepta- 

 cles, which open into as many openings on the edges of the ninth and 

 tenth, as well as the tenth and eleventh, segments, and during copula- 

 tion are filled with sperm. The male sexual organs consist (1) of two- 

 pairs of testes, which, formed like the ovaries, lie in the tenth and elev- 

 enth segments, and (2) two seminal ducts, which begin with four trum- 

 pet-shaped openings, and terminate externally on the fifteenth segment, 

 and (3) two seminal vesicles with several flaps and nnited by a cross- 

 band and enveloped by the testes and trumpet-shaped mouths of the 

 seminal ducts. Sexual union is reciprocal, each worm impregnating 

 the other, and it takes place in June and July in the night-time. The 

 worms lie with their ventral surfaces opposed, each stretched out so 

 that the opening of the seminal receptacle of one is opposed to the girdle 

 of the other. (See Fig. 31.) 



During the act the sperm passes out to the opening of the seminal 

 ducts, flows in a groove along the body to the girdle, and from thence 

 into the seminal receptacle of the other worm. The eggs are very small, 

 and contained in acapsule (Fig. 31) ; but, as a rule, only one egg develops 

 a worm, the others addling. Fig. 31 illustrates the mode of pairing in 

 the earth-worm and the development of the embryo from the egg of 

 Lumhricns ruhellns Grube, observed in Russia by Kowalevsky. The 

 eggs of Lutnbricus rubellus were found in dung, inclosed one in a single 

 capsule. The European L. agricola lays numerous egg-capsules, each 

 containing sometimes as many as fifty eggs, though only three or four 

 embryos are to be found in a capsule (Kowalevsky). 



INSECTS INJURING THE RADISH. 



The Radish-Fly, Anthomyia radicum Bouch6, A. raphani Harris. — Eating the roots 

 of youug radishes, particularly in old soils; small white maggots, which change \o 

 barrel-shaped, reddish pupa-cases, from which about the first of Juue emerge small, 

 ash-colored flies, with a silvery-gray face, copper-colored eyes, and a brown sjtot on the 

 front of the head, with faint brown lines on the thorax, and a longitudinal black line 

 on the abdomen, crossed by narrower lines. 



Soon after early-sown radishes come up, the roots are attacked by 

 small white maggots, and when the plants grow in old soil the maggots 

 are especially destructive, as I have found them in Maine over twenty 

 years since, when the cup was badly infested. The plants were not al- 

 ways killed, but the roots were so worm-eaten as to be unfit for 

 the table. Though we raised the fly in abundance, we made no notes of 

 it at the time, and copy a description of the larva?, pupa, and fly from Dr. 

 Fitch's Eleventh Report. Our figures (Plate LXIII, Fig. 2) are copied 



