146 Mr. J. W. Fewkes on Angelopsis. 
subject. When this gentleman was last at the Museum [ 
asked him how it was that he had obtained no male speci- 
mens of Ff, Hildebrandti, and very much to my surprise and 
pleasure found (though he had forgotten to mention it before) 
that he had not only arrived at the same conclusion as my- 
self, but had solved the riddle long before on Kilima-njaro, 
and discovered that /. Altumiis the male and F. Hildebrandte 
the female of one and the same species. 
Mr. Hunter had been considerably exercised in his mind by 
on the one hand never being able to obtain the male of J. 
Hildebrandt’, while on the other hand all the specimens he 
got of #. Altumt proved invariably to be males. As these 
two birds were always obtained in company by his collectors, 
the truth gradually dawned on him and was subsequently 
proved beyond a doubt by the dissection of a large number of 
specimens obtained for food. 
On comparing the two birds the different points of resem- 
blance are at once seen, viz. the plumage of the upper surface 
and under tail-coverts and the colour of the bill and legs, 
which are ail practically the same in both ; but, so far as 1 
know at present, the extraordinary difference in the colour of 
the under surface in the sexes is unique in this genus. A still 
more extraordinary thing is that m the two apparently 
closely allied forms, F. dcterorhynchus and F. natalensis, 
the females resemble the males but are without spurs. 
The name Francolinus Hildebrandti, Cabanis, must there- 
fore be used in future to designate this species. 
XVI—On Angelopsis, and its Relationship to certain 
Siphonophora taken by the ‘Challenger. By J. WAUTER 
FEWKES. 
[Plate VII. figs. 1-3.] 
ONE of the most interesting genera of Medusz discovered in 
the depths of the Gulf-stream by the United States Fish- 
Commission steamer ‘ Albatross ’ is a new Physophore which 
was described a few years ago (1884) under the name of 
Angelopsis in my paper on the Meduse of this region. 
This genus is remarkable for its large float and the reduc- 
tion in size and increase in thickness of the walls of the 
polyp-stem, which has the form of a semicartilaginous expan- 
sion with a cavity, and with its external walls covered with 
