ee Ww RURE 
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THURSDAY, MARCH 2, 1882 
AMERICAN ANTS 
The Honey Ants of the Garden of the Gods, and the 
Occident Ants of the American Plains. By Henry C. 
McCook, D.D. (Philadelphia; Lippincott and Co., 
1882.) 
OOKING to the extensive and systematic work 
which Dr. McCook has already accomplished in the 
study of some of the most interesting species of New 
World ants, we are exceedingly glad to observe from this 
additional volume that he has now turned his serious 
attention to the honey ants, for, although the habits of 
this species were known to be certainly among the most 
remarkable of the many remarkable habits that are pre- 
sented by the Hymenoptera, they have not hitherto 
engaged the study of any competent observer. As he 
himself observes, “ Very little of their habits has hereto- 
fore been known, and only the forms of the honey-bearer 
and worker-major. In order, if possible, to remove this 
reproach from entomclogy, I started in the early part of 
July, A.D. 1879, for New Mexico.”’ 
In giving a short abstract of the results which have 
rewarded his energy, we may best begin by describing the 
forms or “ castes’? which Dr. McCook found to constitute 
a colony of honey ants. There are (1) three castes of 
workers, namely, major, minor, and minim or dwarf—the 
first being 8} mm. in length, the second 7 mm., and the 
third 54mm. (2) Honey-bearers, “a sedentary class or 
caste distinguished by abdomens distended into a spheri- 
cal form of expansion of the crop filled with grape sugar: 
the length (including abdomen) is 13 mm. (one-half inch) ; 
the proportions and description of the head and body are 
those of the worker-major, of which it may bea developed 
form.’’ (3) Female, or queen—length 13mm. (4) Male 
—length 5 mm. 
Regarding the economy of the hive, the first important 
point established by Dr. McCook's observations is that 
the honey-bearers do not, as has been asserted, themselves 
elaborate the honey, but that this is gathered by the 
workers from a peculiar kind of vegetable gall, and by 
them poured into the crop or proventriculus of the honey- 
bearers ; the honey-bearers are therefore nothing more 
than living store-houses for the food of the hive, their 
relation to the rest of the community being, as Dr, 
McCook observes, similar to that of the honey-comb 
cells to the hive bee. For not only do the worker-ants 
store the “rotunds,” but when they require food they go 
to the rotunds, which feed them by pressing out a drop of 
their store from the cesophagus. Likewise “the queen, 
virgin females, males, and the teeming nursery of white 
grubs’’ are all dependent on the rotunds for nourishment. 
The honey is collected from the galls by the workers at 
night, the insects being very intolerant of sunlight, and 
quickly dying when exposed to it. The honey pressed 
from the body of the rotunds has a pleasant taste, some- 
what resembling ordinary honey, but more aromatic, 
slightly acid, and contains a larger proportion of water— 
being, therefore, more limpid. It requires about 1000 
honey-bearers to yield one pound weight (troy) of honey. 
Dr. Wetherill says, as the result of analysis, that the | 
VOL. xxv.—No. 644 
substance is ‘‘a nearly pure solution of grape-sugar which 
is in a state of hydration isomeric with grape-sugar, and 
differing from grape-sugar in not crystallising.”’ 
The working ants are so fond of the honey stored 
within the rotunds, that when, in making sections of the 
nests, Dr. McCook ruptured the abdomens of the rotunds, 
he always observed that, “ notwithstanding the high state _ 
of excitement which pervaded the colony, the ordinary 
instinct to defend the nest and preserve the larve, cocoons, 
and other dependents, was at once suspended in the 
presence of the delicious temptation.” It is therefore the 
more remarkable that when a rotund dies the workers do 
not open the abdomen to get at the contained honey, but, 
after severing the abdomen from the thorax, remove each 
part separately to a “cemetery,’’ or common burying- 
ground which these ants, like many other species, main- 
tain. The author suggests, and not improbably, that this 
forbearance on the part of the workers may be explained 
as ‘the result of an instinctive sentiment by which Nature 
guarantees protection to the living honey-bearer.”’ 
The partly-filled rotunds are not wholly dependent for 
their food upon the gorging process to which they are 
submitted by the workers, for when only partly filled, 
they will feed themselves on sugar; but the author 
never saw ‘‘a honey-bearer of full rotundity taking food 
or drink.” But the fact that before this insect is largely 
distended with honey it will feed itself points to the sup- 
position that it may be itself a worker, slightly, if at all 
modified in structure; and this supposition is borne out 
by anatomical investigation. For the latter has shown : 
(1) ‘fthat it is the cvop alone which contains the nectar 
received at the mouth”; (2) “that the organs of the 
abdominal portion of the alimentary canal are ordinarily 
in a natural state, except in so far as their position has 
been changed by the downward and backward pressure 
of the expanding crop” ; and (3) “that the process by 
which the rotundity of the honey-bearers has probably 
been produced has its exact counterpart in the ordinary 
distension of the crop in over-fed ants ; that at least the 
condition of the alimentary canal in all the castes is the 
same, differing only in degree, and therefore the proba- 
bility is very great that the honey-bearer is simply a 
worker with an overgrown abdomen.’ ‘Why the extra- 
ordinarily distended crop seen in the honey-ant should be 
limited to two species (so far as known), and why so 
limited a number of workers in the formicaries of these 
two species should develop the round abdomen, are ques- 
tions that provide sufficient wonder, but yield scant 
satisfaction.” ; 
The degree of distension which the crop of a fully- 
gorged rotund undergoes is certainly most surprising. 
Among the thirteen plates with which Dr. McCook’s work 
is illustrated, several figures are given of the crop in 
various stages of repletion. In the comparative scale of 
representation adopted, the empty crop is drawn about 
the size of a pea, and the fully distended one about that 
of a tennis ball. 
Regarding less special points of interest, we may notice 
the “absence of individual beneficence.’’ Not a single 
instance of such beneficence was noticed, although closely 
watched for, while the exhibitions of an apparently cruel 
neglect were many. Thus, “the grains of sand and soil 
were heaped around the rotunds, until the poor creatures 
U) 
