5O J. F. McCLENDON. 



in the first cleavage furrow. This is probably due to the great 

 inequality in the first cleavage. Furthermore, the blastopore 

 does not close at a point diametrically opposite to the first polar 

 body, but considerably posterior to such a point. From a study 

 of the literature on gastrulation in Crustacea, I am led to believe 

 that the blastopore in the majority of cases in this group closes 

 posterior to the vegetal pole and such a character would be 

 accentuated by flattening of the egg. As the eggs occur in single 

 linear series in an egg string surrounded on all sides by sea 

 water, there is probably nothing in the surroundings that could 

 determine the axes of the egg, and we should regard them as 

 probably determined by the structure of the protoplasm. 



VII. SUMMARY. 



1. In the maturation of the eggs of parasitic copepods the 

 behavior of the chromosomes in regard to the question of reduc- 

 tion is very similar to the same process in the free living copepods, 

 yet I differ from Haecker as to the reducing division, considering 

 the first maturation division most probably to be the reducing 

 division. 



2. In the spermatogenesis only a small proportion of the 

 spermatids become spermatozoa. Many spermatids degenerate, 

 others become metamorphosed into peculiar nutritive cells. The 

 protoplasm of the nutritive cells degenerates leaving only a sphere 

 of deutoplasm " Austreibekorperchen," which C. Heider ('79) 

 thought was a glandular secretion. 



IX. ABBREVIATIONS. 



n = Nucleolus. 

 / = First polar body. 



s = Sphere of protoplasm, probably an abnormal structure 

 x -= Darkly staining cell in yolk. 

 y = Yolk spherule. 



