GREGARINA OP EARTHWORM. 369 



Nischney-Novgorod, and in the kidneys of a patient who 

 died from Bright's disease, bear very strongly on the nature 

 of these bodies. The people of Novgorod are believed to 

 get these parasites from washing in water in which Grega- 

 rinoe abound. 1 The most interesting inquiry which is 

 placed before us by these various facts is whether, as 

 Professor Leuckart has observed, "the psorospermiae " 

 (and we may add the " spurious entozoa " of cattle, and 

 even many so-called Gregarinae) are to be considered as 

 the result of a special animal development, or whether 

 they are the final products of pathological metamor- 

 phosis. 



It appears, from the reseaches of M. Claparede and 

 others, that some of the unilocular forms do present very 

 curious, elongated, and active forms, which, from their 

 movements and general appearance, might be mistaken for 

 nematodes. Dr. Joseph Leidy has, in the " Transactions 

 of the Philadelphia Society, 1853," denied the fact that 

 the Gregarince are unicellular animals, on the following 

 grounds : In the examinations of some new species of 

 Gregarince which he has described, and also in the 

 G. Blotharum of Siehold, he discovered that the membrane 

 enclosing the granular mass of the posterior sac was 

 double. He observes : " Within the parietal tunic of the 

 posterior sac is a second membrane, which is transparent, 

 colourless, and marked by a most beautiful set of exceed- 

 ingly regular parallel longitudinal lines." 



M. Leiberkiihn contributed a very elaborate paper 

 on the Gregarina of the earthworm. He does not express 

 any very decided opinion upon the two questions which 

 have been discussed by Leidy and Bruch, but devotes the 

 principal part of his memoir to the development and re- 

 production of the Gregarinse. With regard to the develop- 

 ment of Gregarinae into a filaria-like worm, which Bruch 

 thought probable, M. Leiberkiihn says but little, but, 

 nevertheless, has proved beyond doubt that the nematodes 



(1) Many vague and improbable statements appeared at one time on a sup- 

 posed discovery of Gregarinae in the human hair. Upon a more careful exami- 

 nation being made by competent persons, the foreign body proved to be a well- 

 known vegetable fnngus, often found associated with a disease, or dirty 

 neglected stat t of the skin. It is very well known that Gregarines are neve* 

 found on free jr exposed surfaces. 



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