914 THE VOYAGE OF H.M.S. CHALLENGER. 



inner of which appears to be a little more robust than the outer, which however is slightly- 

 longer and furnished with one or two hairs near the distal extremity. 



The second pair of antennae has the first two joints short and robust, the first joint 

 being implanted beneath the carapace considerably posterior to the frontal margin, and 

 in which Suhm observed the green gland to be present ; the second joint at the outer 

 angle supports a large scaphocerite that is slender at the base and broad at the distal 

 extremity, which is rounded, fringed with hairs, and armed on the outer margin with a 

 strong tooth. On the inner angle of the second joint stands the third and terminal joint 

 of the peduncle, at the extremity of which there is a slender multiarticulate flagellum, 

 which is broken off at about half the length of the carapace ; each articulus being armed 

 with a small point. 



The oral appendages I have not dissected out, but in situ they appear under careful 

 observation to correspond generically with those already described. 



The first pair of gnathopoda is situated posteriorly to the oral appendages, sub- 

 equally with the distance of the latter from the frontal margin ; it resembles the other 

 appendages but has the shaft of the basis smooth and is not quite so large. 



The second pair of gnathopoda, as well as all the pereiopoda, is armed with a sharp 

 and long tooth near the middle of the basisal shaft and another at the anterior extremity 

 of its distal angle ; there are several on the ischium of all the pereiopoda. The posterior 

 pair is rather smaller and less armed with teeth. The seventh appendage or the fifth 

 pair of pereiopoda is not present, nor can I see any trace of it, although in other respects 

 the animal appears as far advanced as the specimens of Amphion reynaudii. 



The first pair of pleopoda (p) is developed as a long cylindrical, slightly curved, 

 uniarticulate rod, the extremity of which is rounded. 



The second (q) and following pairs resemble each other ; these are short and consist of 

 a peduncle that is broad and supports two branches which are subequal in length with the 

 basal joint, the inner is a little shorter than the outer and supports a small and in this 

 stage rudimentary stylamblys. 



The posterior pair of pleopoda forms part of the rhipidura ; the outer plate is broader 

 and longer than the inner, the distal and inner margins are fringed with long hairs and 

 the outer margin is slightly serrate near the distal extremity, where it is also armed with 

 a strong tooth. 



The telson is long, slender, and tapers to a point, the extremity of which appears to 

 be minutely forked, the points of which in our specimen being worn. 



The internal structure is not so well preserved or so plainly marked as in some of the 

 other specimens, but a mass of cellular tissue corresponds with that which in Amphion 

 reynaudii I have thought to be the testes, but which in this specimen vary somewhat in 

 appearance, which I believe may be attributed to the manner of its preservation. 



The brephalos of Amphion has not yet been observed, and the form hitherto known 



