1885.] NATURAL SCIENCES OF PHILADELPHIA. 21 



ments to within ten behind the clitellum, were all living and had 

 regenerated some portion of the excised part. 



The manner of regeneration of the excised anterior five seg- 

 ments had been : — 



1. A union of the outer coat of the body with the lining of the 

 alimentary canal, roughly healing the wound. 



2. A prolongation of these coats, forming a translucent white 

 tube which could be protruded from and retracted into the pro- 

 jecting border of the wound. This tube was at first but a third 

 or a half the diameter of the body. 



3. The formation of the lip or proboscis on the superior side 

 of the end of the tube. 



4. Segmentation proceeding from the anterior end of the 

 regenerated part backward, until the normal number of segments 

 were reproduced. 



5. The deposit of coloring matter in the epidermis of the new 

 segments, and their enlargement to the diameter of the old seg- 

 ments. 



Reference was made to the observations published by Dr. 

 Biilow in the "Archiv fur Naturgeschichte," 1882. 



Miss Fielde now further reports having found a completely 

 regenerated brain, oesophageal collar, and suboesophageal ganglion, 

 all of normal size and in normal site, in earthworms, which had 

 fifty-eight da} r s previous been decapitated at the fifth segment. 

 The worms had been kept in earth, at a temperature of about 60°. 



The precautions taken to ensure accuracy in these observations 

 had been, first, a thorough examination of all the earth into 

 wbich the decapitated worms were put, making it certain that the 

 earth contained no other worms than the decapitated ones; 

 secondly, care that nothing containing earthworms was at any 

 time added to the earth in which the decapitated worms were 

 kept; thirdl}', repeated examinations, at intervals of less than a 

 week, of all the earth holding the decapitated worms, and the 

 careful removal of minute worms bred therein ; fourthly, frequent 

 counting of the decapitated worms, with examination under a 

 lens, the evident wound constantly showing that the worms under 

 observation were the individuals decapitated. The paler color of 

 the new portions also distinguished these worms from others. 



Forty days after decapitation, the excised segments had been 

 regenerated, so' as to present an external appearance of complete- 

 ness, but no brain was visible in dissection. Forty-five days after 

 decapitation the blood-vessels were seen ramifying on the com- 

 pletely regenerated pharynx in a normal manner, but no brain 

 was found. In one of the worms dissected on the fifty -eighth 

 day after decapitation, the suboesophageal ganglion and the 

 oesophageal collar were found to be complete and of the normal 

 size, but the brain lobes were of but half the normal size, and 

 were separated by an interspace of the width of one of the lobes. 

 The blood-vessels united normally on the median line between 



