314 DR. H. GADOW ON THE INTESTINAL [May 2i, 
point out in a few words what are the points which connect them 
with each other; but still, in spite of many important diversities, 
there is something in the organization of the whole of their alimen- 
tary system which tells the experienced eye that the majority of 
them are allied together, and differ from the rest of the birds. 
However, this sounds vague, and is not an exact mode of discussing 
the affinities of the birds in question. 
The lowest Coracornithes are the Coceyges; this name is intended to 
comprise the Cuculidz and the Musophagide. The Cuculide@ possess 
four intestinal loops, of which the second and first are right-handed. 
The loops are on the whole orthoccelous, but the apices of the two 
middle ones are often turned up, or the second loop is plagioccelons. 
Moreover, they possess fully-developed ceca. In all these respects 
they resemble to a great extent the Gallinee; and this hint is con- 
siderably strengthened by Opisthocomus, which is, barring special 
features, exactly intermediate between the Cuculidz and the Galline. 
This is a conclusion which Huxley, Fuerbringer, and others have 
arrived at on independent grounds. The Musophagide (Corythaix 
only examined) possess but three loops, of which only the first is 
right-handed. So far as the other two are concerned, they are 
isoccelous birds, and agree in this point with the bulk of the Corac- 
ornithes. The decreased number of loops of Corythaix is the 
result of the shortening of the gut, a feature always connected with 
frugivorous habits. I consider that the second loop of the Cucu- 
lidee has been suppressed in the Musophagide, and that conse- 
quently their last two loops correspond with the third and fourth of 
the Cuculide. The isoccelous feature of the Musophagid is 
therefore reduced to a secondarily acquired one, and to a case of 
convergence towards the typically isoccelous birds. ‘The Coccyges 
are therefore, like Opisthocomus, birds which have sprung from the 
Gallinaceous stock, ard have followed lines of development which 
are directed towards the Coracornithes, and which in the Muso- 
phagide have attained their highest features. 
The Picide, Capitonide, and Rhamphastide are very close allies, 
and form the Pici. They differ, like the Epopes (Bucerotide and 
Upupidz) from all the other Coracornithes in the alternating posi- 
tion of their four loops, which, in the frugivorous Rhamphastide, 
and in the likewise extremely short-gutted genus Upupa, are reduced 
to three by the suppression of the original second loop. Xantholema, 
one of the Capitonide, has this second loop still indicated. The 
total absence of czeca in all these birds is a coincidence, whilst there 
are no obvious characters, besides the anticcelous convoluticns, which 
point to a close relationship between the Pici and the Epopes. 
There remains the large congregation which is, in the diagram, 
included in the isoccelous circle. Of these the Coraciide stand 
nearest to the hypothetical ancestral or central stock, because they are 
the most generalized set, from which all the others can be derived. 
In one direction started from or out of the Coraciidze the d/cedinide, 
which have reached a truly mesogyrous formation. Their lengthened 
gut,.in conformity with their partly piscivorous habits, forms a left- 
