AIKINETOCYSTIS. 73 



Dimensions. — Maximum size 130 fi by 19 [i, minimum 70 ju. by 

 12/x. 



Eemarhs. — The parasites lie coiled and contorted among the 

 coelomic corpuscles and the genital products of the host, and 

 are never attached to the body- wall or the gut. There is no 

 organ of attachment to the host. The body is cylindrical, 

 resembhng an elongate Nematode worm, with more or less 

 parallel sides and tapering slightly towards the extremities 

 of the united pair. Attachment takes place by means of the 

 tapering end of an individual fitting into a regular concave 

 hemispherical depression of the other. The ratio of width 

 to length of each individual is about 1 : 6. Ectoplasm is 

 thin. Endoplasm is coarsely granular, and the stream of 

 granules flows very swiftly and uniformly from one end of 

 the trophozoite to the other, going backwards and forwards 

 in a straight line. The nucleus measures 17 /x by Qfi, and Ues 

 with its long axis parallel or shghtly inclined to the sides of 

 the body. 



The associating pairs become short and pear-shaped and 

 later rounded off. Gametocysts not found. Sporocysts 

 spindle-shaped, with the two ends finely pointed, 29-35 ju, 

 by 6-4 fi. 



Habitat. — Coelomic cavity of Dendrostoma signifer Sel . & de 

 Man : Andamans, Port Blair. 



5. Family AIKINETOCYSTIDiE Bhatia, 1930. 



Trophozoites solitary or adherent, branching dichotomously, 

 the branches serving for the attachment of the parasite to the 

 host. Sporocysts as in Monocystis. 



Genus AIKINETOCYSTIS Gates, 1926. 

 Aikinetocystis, Gates, 1926, pp. 400-4 ; Bhatia, 1930, p. 160. 



Trophozoites cyHndrical or columnar, with a characteristic 

 regular, dichotomous branching at the attached end, with 

 sucker-Hke bodies borne on the ultimate branches ; sohtary 

 or in groups of three to eight. Sporocysts as in Monocystis. 

 Coelomic parasites in various species of Eutyphoeus. 



18. Aikinetocystis singularis Gates. (Fig. 20.) 



"f Aikinetocystis singularis. Gates, 1926, pp. 400—4, figs. 1—3. 

 Aikinetocystis singularis, Bhatia, 1929, p. 126 ; 1930, p. 160. 



Trophozoite cylindrical or columnar, with a characteristic 

 regular, dichotomous branching at the attached end ; fixation 



