270 MR. FORBES ON THE PTERYLOSIS OF MESITES. [Feb. 21, 
The third patch is inferior in position, lying just at the commence- 
ment of the pectoral region, between the two halves of the inferior 
tract internally and the anterior extremity of their separated pec- 
toral branch externally. 
The fourth patch is longer and narrower than its fellows, lying on 
the ventral region just outside the middle part of the inferior tract. 
The /ifth (lateral) patch lies more or less transversely, in the 
neighbourhood of the axilla, between the posterior ends of the outer 
pectoral and humeral tracts. 
No Ardeine bird has any such lateral pair of patches; and only 
Cancroma has the anterior dorsal pair. These moreover lie outside, 
and not znside, the dorsal tracts in that bird. On the other hand, 
the concentrated patches of Mesites may easily be derived from the 
more diffused arrangement found in Rhinochetus* and Eurypyga. 
A full account of the pterylosis of Rhinochetus is still a 
desideratum, Dr. Murie having unfortunately omitted any account 
of the systematically more-important contour-feather tracts in his 
account of the “ dermal structures ” of the Kagu (J. c.). 
Ihave at present insufficient material to describe these thoroughly, 
though an examination of two imperfectly-feathered specimens in 
spirit demonstrates considerable agreement between the Kagu and 
Mesites. Of Eurypyga we likewise have but imperfect information, 
due to Nitzsch*, and not to my mind very satisfactory, judging 
from the material before me. 
In Rhinochetus, as in Mesites, the neck-feathering is quadriserial, 
though the median dorsal space is much narrower below and the 
lateral neck-spaces very broad ; the two dorsal tracts terminate close 
together about the level of the anterior end of the scapule, and are 
quite separate from the posterior portion, which is only forked to a~ 
slight extent anteriorly, and widely dilated mesially. These differences 
seem to be due mainly to the greater development of the dorsal 
powder-down tracts of Rhinochetus, these covering most of the 
dorsal aspect of the trunk, except a narrow median space along the 
backbone and a reversed heart-shaped area on the pelvis, to which 
spaces therefore the contour-feathers are nearly confined. 
Below, as in Mesites, the inferior tract of each side is nearly or 
quite broken up into two by the interruption of a patch of powder- 
down feathers; and the pectoral branch is likewise quite separated 
from the main tract, as in no other bird known to me except Mesites, 
powder-downs also intervening between the two. The humeral tract 
is quite free from the inferior one. On the other hand, in the 
number of its rectrices (16), and the absence of an aftershaft to 
the feathers, Mesites differs from EZurypyga and Rhinochetus, both 
of which have 12 rectrices* and an aftershaft. The number of 
primaries in all is 10. 
Mesites, Rhinochetus, and Eurypyga agree together, but differ 
from the Rallid@, in having well-developed and strong rectrices, in 
ee 8. vii. pl. 56. figs. 1-3. 
 *Pterylography,’ Ray Soe. ed. p. 129, pl. viii. fig. 15. 
8 Prat ie a not 10, as pat ieee E stated by Murie, loc. cit. p. 468. 
