GENERAL BIOLOGY 



bits of hyaline protoplasmic cells. Each develops an 

 organ for the penetration of the wall and attachment to a 

 single digestive cell, from which, during the early part of 

 its life it draws its nourishment. 

 Later it becomes free, and grows 

 enormously, without dividing. As it 

 increases in size its endosarc be- 

 comes charged with an abundance of 

 absorbed food materials, and takes 

 on the dark and granular appearance 

 already noted. 



This long period of growth and 

 accumulation of food materials is 

 followed by one of rapid and exten- 

 sive cell division outside the body of 

 the grasshopper. Late in the season, 

 when the grasshoppers and crickets 

 also are old, most of the gregarines 

 are found attached end to end in 

 pairs. This looks like conjugation 

 at first sight and has been so inter- 

 preted in the past ; but it is only ap- 

 position, preparatory to further de- 

 velopment. In such pairs, the pro- 

 toplasm will often show a different 

 appearance in the two individuals. 

 One cell of the pair divides into a 

 very large number of motile sperm 

 cells, the other into a smaller number 

 of egg cells : the separating walls be- 

 tween become dissolved and eggs and sperms are comming- 

 led in the common interior, and fuse in pairs. 



Each of the fertilized eggs divides three times into eight 

 minute cells which take on an elongate and somewhat boat- 



<oo 



FIG. 68. Gregarine from 

 the stomach of a grass- 

 hopper, a, a single in- 

 dividual, showing the 

 dense granularity of the 

 protoplasm; b, a group 

 of individuals, apposed 

 mostly in pairs, as they 

 appear previous to sex 

 cell formation. 



