314 DR. H. GADOW ON THE INTESTINAL, [May 21, 



point out ill 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 Coccyges; this name is intended to 

 comprise the Cuculidre and the Musophagidae. The Cuculidce 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 plagioccelous. 

 Moreover, they possess fully-developed caeca. In all these respects 

 they resemble to a great extent the Gallinae ; and this hint is con- 

 siderably strengthened by Opisthocomus, which is, barring special 

 features, exactly intermediate between the Cuculidas and the Gallinae. 

 This is a conclusion which Huxley, Fuerbringer, and others have 

 arrived at on independent grounds. The Musojihayidce {Conjthaix 

 only examined) possess but three loops, of which only the first is 

 right-handed. So far as the other two are concerned, they are 

 isocoelous 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- 

 lidse has been suppressed in the Musophagidae, and that conse- 

 quently their last two loops correspond with the third and fourth of 

 the Ciiculidae. The isuccelous feature of the jNIusojjhagidie is 

 therefore reduced to a secondarily acquired one, and to a ca^e of 

 convergence towards the typically isocosloiis birds. The Coccyges 

 are therefore, like Opisthocomus, birds which have sprung from the 

 Gallinaceous stock, and have followed lines of development which 

 are directed towards the Coracornithes, and which in the jNIuso- 

 phagidse have attained their highest features. 



The Picidce, Capitonidcp, and lihamphastidcs are very close allies, 

 and form the Pici. They differ, like the Epopes (Bucerotidae and 

 Upupidse) from all the other Coracornithes in the alternating posi- 

 tion of their four loops, which, in the frugivorous Khamphastidaj, 

 and in the likewise extremely short-gutted genus Upvpa, are reduced 

 to three by the suppression of the original second loop. Xuntholcema, 

 one of the Cajjitonida?, has this second loop still indicated. The 

 total absence of caeca in all these birds is a coincidence, whilst there 

 are no obvious characters, besides the anticcelous couvohitii ns, which 

 point to a close relationship between the Pici and the Epopes. 



There remains tiie large congregation which is, in the diagram, 

 included in the isocoelous circle. Of these the CoraciidcE 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 CoraciiiUe i\\e Alcedinidce, 

 which have reached a truly mesogyrous Ibrmation. Their lengthened 

 gut, in conformity with their partly piscivorous habits, forms a left- 



