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THE AMEBIC AX NATURALIST [Vol. XLIII 



immersed. If it lives in the stomach of the host, for in- 

 stance, the reaction would probably be alkaline and the ac- 

 tion of the digestive juices would thus be neutralized. In 

 other locations the reaction would be different and might 

 be very complex. 



A small minority of investigators, however, but im- 

 portant and influential though small, does not believe in 

 the glandular function of the subcuticular cells. Rind- 

 fleisch and Leuckart (1886, p. 366) first expressed the 

 opinion that, in cestodes at least, they are simply pecul- 

 iarly formed connective tissue cells which in certain places 

 may lose their spindle form and assume quite the form of 

 ordinary parenchyma cells. This is the case, for instance, 

 as already stated, in the scolex and between the pro- 

 glottids. 



Looss (1893) also regards the subcuticular cells as 

 connective tissue structures, interpreting them as embry- 

 onic and unspecialized cells which are destined to develop 

 jnto parenchyma and muscle strands as the worm in- 

 creases in size, and he supports his views with such a 

 mass of detailed observations and such cogent reasoning 

 that it is likely they would be generally adopted if the 

 belief in the secretory nature of the subcuticular cells 

 were not so firmly fixed in the literature of the times. 



Looss shows that the interior cells of the germ-balls of 

 the cercaria develop into the nervous system, the genital 

 organs, the intestinal co?ca and the parenchyma — all after 

 the first appearance of the cuticula. But all of these cells 

 do not at once so develop. The young worm must grow 

 often many thousandfold before it reaches adult size, 

 and this increase in size is made possible through the 

 persistence in an undifferentiated condition of certain of 

 these interior embryonic cells, which during the life and 

 growth of the worm are constantly forming new paren- 

 chyma cells, as well as other structures. The formed 

 parenchyma cells do not divide. In the cercarian tail, 

 which is destined to have but a very short existence, all 

 of these cellular elements become parenchyma cells and 



