xii
the oil-gland. Anteriorly the two divisions of the spinal tract arc connected liy scattered
feathering with the humeral tract. The ventral tract is double from close to its point of origin
at the mandibular symphysis ; the two tracts arc at first very narrow, and separated from each
other and from the sides of the head by spaces without any feathering: on the pectoral region
each ventral tract is of uniform width, four or live feathers wide ; below the axilla each tract gives
off a closely feathered lateral branch to the hypopteron. The pectoral tract of each side dwindles
to a single row of feathers before ending just in trout of the cloaca.
" The pterylosis of Merojps docs not differ in any important respects from that of Coracias,
which it appears most closely to resemble ; it differs from Moinotus and Twins in having a double
spinal tract, and from Galbitla in having no inner branch lo the pectoral tract running along
the clavicles.
"OSTEOLOGY.
" T h e characters of the skull of Merops have been dwelt upon by Prof. Huxley, in his wellknown
paper on the Classification of Birds. The skull is desmognathous, and the family is placed
in the group Coccygomorpha1 , in close proximity to the Aleedinidie, Bueerotidie, Upupida;,
Momothhe, and Coraciidie. In the same paper the author refers to the shape of the sternum in
t h e Coccygomorpha', which is stated to present usually two notches on each side, and to be devoid
of a bifurcated manubrial process, the one exception to the last statement being Merops. I find,
however, that Trogon (T. re'tnhardti) has a distinctly bifurcate manubrial process, though
not perhaps so well marked as in Merops. The characters of the skull of the former genus,
which has been shown by Mr. Forbes to be schizoguathous and not desmognathous, would appear
to necessitate its removal altogether from Huxley' s group CoccygomorphfiB, though it undoubtedly
agrees in its visceral and muscular anatomy, as well as in external characters, with the other
families of this order, and presents affinities to Merops, as well as to the Oeleomorpha; and
Coracomorpha?, by t h e possession of a forked manubrium sterni.
" T h e sternum of Merops is, as stated by Prof. Huxley, provided with two lateral notches, of
which the outer one on each side is the deepest; in Coracias, Trogon, 1'teroglossus, Bucco, Dacclo,
and Yitux the sternum is closely similar; in Momotus the notches are converted by continuous
growth into foramina; in XJpupa and Buccros there is only a single pair of notches.
"According to Prof. Huxley the clavicles of the Coccygomorpha1 are without any process
developed backwards from the summit of their ' symphysis.' This statement is true, in so far
that there is no junction between such a process and the sternum as exists in many Passeres, not
to mention other orders of birds ; but the process itself exists, in a rudimentary form, in many of
t h e CocoygomorphsB. In Coracias and Trogon there is such a process developed just at the
junction of t h e two clavicles, and there is t h e faintest trace of a similar structure in Meroj>s. On
the other hand, Upupa, Yunx, Bucco, Momotus, &o. have no median process of the furcula.
xiii
" MYOLOGY.
" The Hempidn agree with all the other families of the order Anomalogonataj of Prof. Garrod
in the absence of the ambiens, and in the presence of the femoro-caudal and the semitemUnosus
and its accessory; the formula, therefore, on Prof. Garrod's system, is—AX Y. With regard to
other muscles which vary in different groups of birds, the Meropida.' possess the so-called expansor
secundariorum, which has the characteristic disposition termed ' Ciconiine' by Prof. Garrod. The
presence of this muscle is not usual among Anomalogonatous birds, but it exists among the
Moinotida:, Alccdinuhe, in Sleatornis, the Coraeiidrc, Eeptosomida?, and Galbulkkc; in the last
three families the expansor secundariorum is Ciconiine, as in Merops.
" The tensor patagii longus arises from the clavicle by two distinct heads, one in common with
the single head of the tensor patagii brccis; the tendon of the latter muscle bifurcates just before
its insertion on to the extensor metacarpi. The termination of the tensor patagii tendon is, in
fact, very closely similar to that of the Galbulidie, especially Vroiptlba parailisea; in Coracias
the tendons of this muscle arc a little more complicated.
"The deltoid extends a long way down the humerus; it receives a fibrous cord from the
scapula, which passes under the latissimus dorsi and over the anconeus tongue. A similar
accessory head to the deltoid occurs in many birds—for instance, among those which have
evident relations to the Bee-eaters, in Momotus, Ugiomanes, Galbitla albirost ris, and Vrogatba
paradise a; in Coracias, as in the Todies, this tendinous slip is absent. The anconeus toiujus is
attached to the humerus about one third of the way down by a tendinous slip, which is inserted
in common with the posterior latissimus dorsi; a similar disposition is met with in Coracias,
Urogalba, and Galbitla; this tendinous accessory head of the anconeus is absent, however, in the
Tollies, and in Momotus, Jlglomanes, Daceto, &c. The deep flexor tendons have been described
by Garrod as more particularly resembling those of Momotus and Dacclo; they differ slightly
from Coracias, and still more from the Galbulidas.
" On the whole the myology of the Bee-eaters seems to indicate a specially close alliance with
the Coraciidie and Galbulidu.1, though there are no wide differences from other families of the
Anomalogonata1 . The presence of casca in the intestine, and the absence of a tuft on the oilgland,
led Prof. Garrod to associate the Meropida? with the above-named families, as well as with
the Trogonidffi and Passeres. The absence of ea?ca and the presence of a tufted oil-gland distinguish
the Hornbills, Colics, Kingfishers, Woodpeckers, and Motmots. The myology of these
different families does not perhaps afford any very strong support to Prof. Garrod's division, but it
is at any rate in no way opposed to i t : it will he noticed from the facts recorded above that the
expansor secundariorum, if present, has a different disposition in the Aves Passcriformes such as
Merops; the accessory head of the anconeus is apparently absent in the Trogonida.1, and often,
if not always, present in the Passeres. The myology as well as other details of the anatomy of
the Oaprimulgidffl arc not perhaps in accord with such a division; but i t appears to me that there
are grounds for removing this group altogether from the Piciforincs or Passeriformes."