Origin of Species Variorum

→ case of the 1859 1860 1861 1866 1869

OMIT 1872

→ has 1859 1860 1861 1866 1869

as in the case of the Molothrus bonariensis, has 1872

→ kinds. 1859 1860 1861 1866

kinds of bees. 1869 1872

→ be necessary 1859 1860 1861 1866

have been indispensable 1869 1872

→ likewise, of Sphegidæ (wasp-like insects) are 1859 1860 1861 1866 1869

of Sphegidæ (wasp-like insects) are likewise 1872

→ on other species; 1859 1860 1861 1866

in the same manner on other species; 1869

OMIT 1872

→ to feed on, 1859 1860 1861 1866

OMIT 1869 1872

→ the supposed case 1859 1860 1861 1866 1869

that 1872

→ cuckoo, 1859 1860 1861 1866 1869

Molothrus or cuckoo, 1872

→ work of any kind, and the workers or sterile females, though most energetic and courageous in capturing slaves, do no other work. 1861 1866 1869 1872

work. 1859 1860

of the

here

hens

laying a large number of

eggs,

eggs;

but, as

with

the →case of the cuckoo, at intervals of two or three days.

The

This

instinct, however, of the American

ostrich,

ostrich

→has not as yet been perfected; for a surprising number of eggs lie strewed over the plains, so that in one

days

day's

hunting I picked up no less than twenty lost and wasted eggs.

Many bees are parasitic, and

regularly

always

lay their eggs in the nests of

~~bees of~~

bees of

other →kinds. This case is more remarkable than that of the cuckoo; for these bees have not only

had their

their

instincts but their structure modified in accordance with their parasitic habits; for they do not possess the pollen-collecting apparatus which would →be necessary if they had

stored

store

up food

food

for their own young. Some

species

species,

→likewise, of Sphegidæ (wasp-like insects) are

parasitic;

parasitic

→on other species; and M. Fabre has lately shown good reason for believing

that,

that

although the Tachytes nigra generally makes its own burrow and stores it with paralysed prey for its own

larvæ,

larvæ

→to feed on, yet

that,

that

when this insect finds a burrow already made and stored by another sphex, it takes advantage of the prize, and becomes for the occasion parasitic. In this case, as with →the supposed case of the →cuckoo, I can see no difficulty in natural selection making an occasional habit permanent, if of advantage to the species, and if the insect whose nest and stored food are

~~thus~~

thus

feloniously

appropriated

appropriated,

be not thus exterminated.

Slave-making instinct .—

This remarkable instinct was first discovered in the Formica (Polyerges) rufescens by Pierre Huber, a better observer even than his celebrated father. This ant is absolutely dependent on its slaves; without their aid, the species would certainly become extinct in a single year. The males and fertile females do no →work of any kind, and the workers or sterile females, though most energetic and courageous in capturing slaves, do no other work.