TO A. HANCOCK, ESQ. ' 273 



positive of this latter fact, and it is the most curious point in the 

 anatomy of the genus. Alcippe must always eject (as other 

 Cirripedes sometimes do) its excrement from the mouth. 



Acoustic and olfactory orifices as in Ibla. Eye not discovered. 

 iN'ervous system hardly examined. 



Female Organ of Generation. — All quite normal, as described 

 under the Lepadidse. The ovigerous frsena are very large, and 

 are destitute (as in some species of PoUicipes) of glands ; they 

 probably serve as branchiae, as well as the universally-admitted 

 branchiae in sessile Cirripedes, of which they are the homologues. 

 Male organs none except a rudiment of penis in normal position 

 between and on ventral side of sixth cirrus. 



I have forgotten to remark that the external parts of animal 

 (capitulum and peduncle) do not essentially differ from same 

 parts in Anelasma, though very peculiar. 



Metamorphoses. — In first stage I can add only the minute and 

 lower antennae. Most fortunately I detected some larvae just 

 before their metamorphosis into Alcippe. They are peculiar in 

 having their prehensile antennae seated almost at the very end 

 of the quasi-bivalve shell ; the abdomen and caudal appendages 

 are peculiar; but they have six pairs of natatory thoxacic legs, 

 and in all other respects resemble the pupae of Lepadidae. 



Male Alcippe. — Almost every female has from one to three or 

 more males attached to her on both sides, externally, near the 

 upper end of the horny shield or disc on the peduncle, in two 

 little bags where I have put a cross. '^^ The male is as transparent 

 as glass; its lower end (answering to the peduncle) is three- 

 lobed, and caricatures the form of the same part in Alcippe ; the 

 other part (or capitulum) is flattened, much produced, and of 

 nearly the same width throughout, with a small orifice at the 

 upper end. Total length -2-<rth of an inch. In the lower part 

 we have an eye, and great testes and vesicula-seminalis. In the 

 capitulum we have nothing but a tremendously long penis coiled 

 up, and which can be exserted. There is no mouth, no stomach, 

 no cirri, no proper thorax ! The whole animal is reduced to an 

 envelope (homologically consisting of three first segments of 



* Sketch given in letter. 



