ALCIPPE LAMPAS. 557 



The male immediately, after the exuviation of the pupal 

 carapace, ^th of an inch in length, is only -^th of an inch 

 long, but ultimately it becomes, chiefly from the growth of 

 the lower end of the peduncle, nearly twice this length; for 

 the largest specimen which I have seen, that figured, was 

 T ^th of an inch long (t. e. under 4th of an inch), and 

 tJoth of an inch in breadth across the peduncle, beneath the 

 lateral lobes. The whole external membrane of the animal 

 (as well as the internal membrane of the sack), is very thin, 

 quite structureless, and as transparent as glass ; hence, even 

 the spermatozoa, within the vesicula seminalis, can be seen 

 from the outside. The whole structure of the animal is 

 very simple. The ventral surface can be at once recognised 

 by the attachment of the antennas (fig. 19, a), and these 

 organs mark the point which was the anterior end of the 

 male, just at the period of its metamorphosis, and before the 

 lower end of the peduncle had grown. These antennas have 

 already been fully described ; they are conspicuous from 

 being composed of membrane, rather thicker than that 

 investing the body of the male, and which external membrane 

 can be traced entering these organs, and appearing like 

 cement-ducts ; but within these tubular prolongations of the 

 outer membrane, I could obscurely see the real cement-ducts. 



The part answering to the capitulum is much flattened 

 and elongated; it widens but little from the upper to the lower 

 end, where it blends with the carinal or dorsal surface 

 (the under surface in fig. 19) of the lobed peduncle. At the 

 upper end there is a small orifice, and close to this, on the 

 ventral or rostral side, there is a thin, apparently double pro- 

 jection [i, fig. 19) or flap of membrane, one flap lying exactly 

 over the other. The whole length of this capitulum probably 

 corresponds with that small portion of the capitulum in the 

 female, between the upward prolongation of the horny disc 

 and the lower end of the orifice; and the two broad flattened 

 projections in the male, probably answer to the two sharp 

 narrow points [a, fig. 1, PL 22) in the female. The peduncle 

 has two lateral lobes {/i,j/, fig. 19), and, whilst young, what 

 may be called a third and medial lobe, but this soon increases 

 largely by growth, and forms the main part of the peduncle. 

 The lateral lobes are intimately connected with the ventral 

 surface ; they tend to lie in a plane, at right angles to the 



