g. \'i>ungest stage observable in the body of Salpa. Egg-cells are still recogniz- 



I02 T. KOMAI : STUDIES ON TWO ABERRANT CTENOPHORES 



5. Individual with body-diameter measuring about 0.3 mm; sketch from materi- 

 al in formalin. 'I'he gastro- vascular cavity is in a form of a single roomy chamber divided 

 peripherally into four subequal pouches. 



6. Stage a little earlier than above; sketch from material in formalin and 

 through the test of host. The gastro-vascular cavity is of a simpU- nnindish form. Notice 

 the assemblage of blood-corpuscles of host around the parasite. 



7. Stage about the same as above; sketch from stained material. Notice egg- 

 cells arranged in a complete circle. 



8. Stage in which the body is nearly hemispherical; sketch from stained 



material. 



able, ffv. 



10. Planula-stage killed while boring the test of the host, with upper half of 

 body lying freely outside and lower half imbedded in the test; sketch from stained material. 

 Notice tlial the entire surface of Ijody is covered with tlagella. 



11. Median vertical section of the most advanced stage; X9o. 'Ihe .section- 

 plane is slightly ol)li(]ue to the sagittal plane of body. Notice the profuse foldings on the 

 ventral surface. 



Figs. 12-14. Three sectitnis from a series of horizontal sections of the most advanced 

 stage; X 100. Throughout the figures the section-plane is slightly oljli(]ue to tlie horizontal 

 jilane and the right half is from a level a little below the left half. 



15. Median vertical section of about the stage in fig. 3; X160. Tlie section- 

 plane is a little oblicjue to the transverse plane of body. 



16. Median vertical section of about the stage in iigs. 6 and 7; X240. 



Plate 9. 



Gasirodes parasiticum. 

 I'ig. I. Median vertical section of a1)oral .sense-organ; X360. 



2. Longitudinal section through a rib; x 500. Tliis ligure also shows a part 

 of vacuolated epithelium of meridional canal underlying the rib. Notice the aggregates of 

 blood-corpuscles of host taken as food-matter. 



3. Tentacular apparatus of the most advanced stage. Horizontal section; X150. 



4. Tentacle-stem. Longitudinal .section; x9oo. 



5. .-\ part of canal wall showing the formation of excretory corpuscle; x6on. 



6. A part f)f \entral epidermis harbouring several egg-cells of \arious develop- 

 mental stages; X900. 



7. Egg-cell amoeboid in appearance; x9oo. 



8. Muscle-fibres showing branchings; X 500. 



9. Median longitudinal section of planula; x 300. 



