8 Mr. F. Muir and Br. U. Sharp on 



series of cells. After the tLiity cells have been formed 

 and the eggs laid, there is then applied a thick chitin- 

 ous covering * forming a hard shell. Outside this 

 shell numerous delicate membranes are applied so as to 

 form many cells about the circumference. A very peculiar 

 structure is thus produced. It has somewhat the shape of 

 an ant-hill or termitarium. 



Not only is the structure itself different in form from 

 the oothecas of the genus Aspidomorpha, but even a single 

 membrane shows characteristic distinctions ; there is a 

 thickening along the middle of each (fig.l6),like the mid-rib 

 of a leaf, and instead of being curvate in transverse section 

 each membrane is slightly angulate. This is due to the 

 shape of the oothecal plates which Muir describes as 

 " indented with a V-shaped cut, the sides of which hardly 

 meet at the apex" of the V (fig. 17). 



6. Oassida muirana. 



PI. II, figs. 18, 19. 



The ootheca of this species is a very small structure 

 consisting of about four cells. It is laid flatly on a leaf and 

 covered with a layer of excrement, from under which the 

 membranes project a little on each side. 



7. Cassida unimacula. 



This species is fairly common at Durban, but we can 

 give very little information as to the ootheca. A specimen 

 of it laid two eggs in a folded membrane in Mr. Muir's 

 breeding cage. So that it is probable the ootheca 

 will prove to be a very small structure as in the case of 

 Cassida muirana. Both of the eggs were subsequently 

 found to be parasitized. 



8. Laccoptcra cxcavata. 



The ootheca is small and usually contains only two eggs, 

 but sometimes four. It is attached to the surface of a leaf 

 of Ipomoia holoseo'icca by a membrane. One or two mem- 

 branes destitute of eggs are placed on the exposed surface, 

 and then the whole is covered with a layer of excrement 



* Mr. Muir thinks tliis is due to a number of membranes plastered 

 firmly together. It may, however, be due to a quantity of colleterial 

 matter applied in some other special manner. 



