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Show 1889.] MR. W. K. PARKER ON STEATORNTS CARTPENSIS. 185 such as Eurystomus and Podargus; not the inhabitants of its own region. The same thing is to be seen in several other types : Dicholophus, a Crane-like bird of prey, represents the Ethiopian Secretary-bird ; the Boatbill (Cancroma), the great Baloeniceps of the Soudan ; and even the Tinamous, which are so closely related to the Ratitae, look more towards Apteryx than towards Rhea. These, however, are a few facts which are mere samples of a very large number, and the organic types generally that lie beyond " Wallace's Line " in the East, are to be compared with those that are from beyond the Isthmus of Panama in the West. As to the group to which Steatornis belongs, I think that at present the best thing to do is to drop some of Professor Huxley's smaller group-terms, and to retain these for larger gatherings of birds. If his " Cypselomorphae," for instance, are allowed to fall back into the great and most important group of the Coccygomorphae we shall get over many difficulties and have a suborder comparable to the Coracomorphae. These two groups, so constituted as to take in, in the latter, all the nEgithognathae except the Swifts, and the former be made to hold within one ideal boundary-line all the non-passerine arboreal " Altrices " (except the Pigeons and Raptorial birds), all the " Tenuirostres," " Fissirostres," " Syndactyli," and " Zygodactyli " of Cuvier,- then the likeness or the unlikeness of the two groups will shine out clearly. In the Coracomorphae we have 6000 species, that, by their most amazing uniformity, suggest to the Evolutionist one common parentage, and in that group only a small percentage of types is abnormal. In some characters, both of the skeleton and of the soft parts, there is an absolute uniformity. I know of no case in which the caeca coli are absent; and from the Corvidae proper to the Pteroptochidae, the most variable part of the skeleton-the manus and pes- the distal part of both fore and hind limbs, are uniform throughout. The carpo-metacarpus has, in every skeleton I have seen, a bony bridge over the proximal part of the interosseous space formed by ankylosis of an ossified cartilaginous plate, which is in reality an intercalary metacarpal. Also in none, except the Bank-Swallow, have I found a developed ungual phalanx to the 1st or 2nd digits; they almost always abort or suppress the 2nd phalanx of the 1st, and the 3rd phalanx of the 2nd digit. In the leg, the tarso-metatarsus always, so far as I have seen, has five tendon-canals behind its head. There is no finished canal here either in Steatornis or in Cypselus; in the Common Fowl there is one passage-a common state of things. Then, as I have said, in the skull there is always that peculiar modification of the Schizognathous palate which Professor Huxley calls the ^Egithognathous type. Also, except in rare cases, the basiplerygoids are nearly suppressed ; only in a few cases are they seen even as thin prickles, in |