EARTHWORM STUDIES. 2C3 



Should all the conditions be satisfactory, the egg soon begins 

 to show signs of life. It is left to nature to hatch, and the time 

 occupied in the process varies greatly. If an egg-case be opened 

 after some time, a tiny embryo worm, or sometimes a pair, will 

 be found inside, surrounded by a glutinous fluid. The young 

 worm as it grows expands its case, and ultimately emerges — not 

 as a caterpillar or larva, for it goes through no metamorphoses as 

 does the butterfly or frog, the sawfly or even the fish, but as a 

 worm ; and now it has only to hasten development and become 

 adult. The adult stage is reached when a girdle has been 

 assumed, just as is sometimes the case among human beings. 



It sometimes happens, however, that things do not go well. 

 I have often observed that the eggs of worms are liable to 

 be rendered abortive by the invasion of a smaller worm. It is 

 another illustration of the amusing rhyme about the big fleas and 

 little fleas. Into the life-history of these parasites, however, I 

 must not now enter, as the subject requires a chapter to itself. 



It would occupy too much space if I were to detail the 

 wonderful process which goes on within the egg-case. The 

 embryology of the worm has been fully studied, and is replete 

 with marvels. If an egg is examined when the young embryo is 

 almost ready to emerge, it will be possible, through the semi- 

 transparent and greatly dilated case, to watch the movements of 

 the worm, trace the current of blood along the elaborate system 

 of vessels, and eventually observe the emergence of the baby 

 Annelid into the world. 



For the further study of this intricate subject, I may refer the 

 reader to Mr. Beddard's valuable Monograph, and the works 

 which are there enumerated. 



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