356 THE AMERICAN MONTHLY [Dec, 



parent. In the blood of Amia calva a slightly different condi- 

 tion is present. Simultaneously with the formation of this true 

 fibrin an additional formation takes place. This is of a jelly- 

 like nature and has been called the additional fibrin. This fi- 

 brin increases uniformly with the increased strength of the salt 

 solutions. George Semmer has investigated a similar formation 

 in the blood of the frog and domestic fowl under slightly differ- 

 ent conditions. He considers that the additional fibrin is pro- 

 duced from the protoplasm of the red cells of the blood by the 

 solvent action of the neutral salts. This additional fibrin is not 

 formed in the blood of mammals, but occurs in that of birds, 

 amphibia (Cry^^tob ranch us, Necturus, Rana), and of a ganoid 

 (Amia). This distinction perhaps makes it possible to draw a 

 stronger line between the nucleated and non-nucleated corpus- 

 cle-bearing animals. The experiments should be extended to 

 the large field of work offered among the Teleosts and other 

 forms of fishes, and also to reptiles, in order to make a sure gen- 

 eralization on this point. 



Blood Corpuscles. — The conclusions of Miss Claypole are 

 as follows: From the measurement and counting of the corpus- 

 cles in Necturus and Cryptobranchus the following facts were 

 ascertained : The cells of Necturus are much larger than those 

 of Cryptobranchus. Comparing this result with the measure- 

 ments given by different authors of the corj^uscles in other forms 

 of amphibia, a distinction can be made on the basis of size of 

 cells between those animals possessing external gills and those 

 without; to which rule, however, a striking exception is found 

 in Amphiuma. In enumeration, also, a difference is shown to 

 exist between the large and small corpuscle-bearing animals, 

 the higher numbers of corpuscles per cubic millimeter belong- 

 ing to the latter class of animals. 



From experiments made on Necturus and Cryptobranchus 

 in the injection of small quantities of carbon into the abdom- 

 inal cavity, hypodermically, the following results were obtained: 

 In the first place, it was established that under the given condi- 

 tions the leucocytes ingested all the foreign material and en- 

 tered the blood circulation after varying periods. In the sec- 

 ond place, it was found that from the blood the ingested cells 

 are distributed to the tissues and ultimately pass away on mu- 

 cous and epidermic surfaces with waste products of the body. 



