trated) of the larva. Spermatogenesis has been briefly described 

 by Sharraa (19A.3). 



Cytology in the kennel tick was studied by Stella (19333), 



who "examined the coiorse of oogenesis and spermatogenesis 



from the larva to the adult (stages) The gonads assume 



their definitive aspect and begin to function only after the last 

 nymphal casting. The maturation with expulsion of both polar 

 bodies occxirs inside the female in the ovary. The fertile sperma- 

 tozoa are formed only in the adult male and are of a unique type 

 with flagellum and undiilating membrane. The chromosomes are 

 probably 48 in number, grouped in twelve tetrads". This paper 

 is nicely illustrated and the reproductive organs of both sexes 

 are described and illustrated. 



Cytoplasmic inclusions in the oogenesis of the kennel tick 

 have been extensively reported by Das (1939), who correlated his 

 own observations with a considerable amount of controversial 

 conclusions by other workers. 



Chromosome studies have been briefly reported by Dutt (1952). 



Adult development vrithin the nymph has been studied by 

 Yalv ac (193'^ 



Excretory habits and mechanisms were investigated by Enigk 

 and Grittner (1952;. 



An " anatomical- physiological study of R. s. sanguineus " by 

 Stella (l9A2j bears conclusions which I have translated freely 

 as follows: 



"(l) In the female, anatomical and histologic differentiation 

 of nDst organs commences with digestion of blood; the gut develops 

 completely and begins to function; the glands begin to ax:tivate 

 secretion; the gonads enlarge and mature. The period of greatest 

 functional activity corresponds nearly to the duration of the 

 meal. Abandoning the host, the female begins oviposition, and 

 during this period completely digests the engorged blood, thus 

 its body, at first turgid and hard, becomes flaccid and soft. 

 The malpighian tubviles by this time are elaborating the substance 



_ 720 - 



