COO ORDER A POD A. 



its appearance into a homogeneous, stiff, pulpy matter, which 

 retained the same appearance all down the threads to within 

 the antennae. This finer matter readily separated from the 

 coarser cellular matter within the sack, but was not divided 

 from it by any septum or membrane. Some way within 

 the threads, the corium, the membrane of the ovarian sack, 

 and the contents appear (e), as seen from the outside, to 

 become, and perhaps really are, blended together. These 

 threads could not have been originally formed of their present 

 length, and must therefore have been added to during the 

 growth of the animal ; but from their entering the not- 

 moulted antennae, and from the animal being permanently 

 attached by them, they cannot have grown, by means of 

 the moulting of their integuments ; hence I conclude that 

 at each period of growth and exuviation they have been 

 added to only at their upper ends, where there is a sort of 

 collar, or line of growth; and where, I may remark, the 

 lining corium is alone well developed. We shall presently 

 see the bearing of these remarks. 



These threads contract to about half their former diameter 

 as they enter the old prehensile antennae of the pupa, within 

 which they are firmly attached. Each thread, with its three 

 tunics apparently blended together, can be traced to the 

 extremity of the disc-segment (j/), where the included matter 

 seems to have burst forth. The whole disc and the terminal 

 segment of both antennae are enveloped, close together, in 

 cement, formed into two almost separate little capsules, by 

 which they adhere very firmly to the integuments of the 

 Alepas. The cement required to be removed before the 

 antennae could be plainly seen. The cement presented all 

 the usual characters, namely, its homogeneous laminated 

 structure and its yellowish colour. The cement in the 

 case of the male Ibla, which is parasitic within the sack of 

 the female Ibla, affects the corium and fibrous matter 

 beneath the chitine-tunic, and causes them to adhere to- 

 gether, and thus prevents the male from being cast off 

 each time that the inner tunic of the sack of the female 

 is moulted : exactly so has the cement of the Proteolepas 

 affected the integuments of the Alepas. The only difference 

 between ordinary cement-ducts and the two threads here 



