2 
POPULAR SCIENCE REVIEW. 
now have been what Ireland lately was.” Without acknow- 
ledging as an undoubted sequitur the above conclusion, we 
must all agree that the turnip has played, and will continue to 
play, a very important part in British agriculture; and his 
name is worthy to descend to posterity who first introduced 
to British field cultivation the variety of the Brassica cam - 
pestris, which we believe to be the origin of our Swedish 
turnip.* 
Probably there is no plant which has more enemies in the 
insect form than the turnip. The late lamented John Curtis, 
whose entomological knowledge is widely known, and greatly 
appreciated, enumerates nearly forty species of insects, besides 
scolopendrae, slugs and snails, which, in a greater or less degree, 
at certain times are found to injure the turnip crops. The 
ants run off with the seed as soon as it is sown ; that which is 
spared by the ants is attacked the moment the tender leaves 
appear above the surface by one of the most formidable, 
albeit diminutive, enemies of all — namely, the little flea- 
beetle, popularly known throughout England as “the fly.” 
Should the crop weather this storm, another blasting influence 
occasionally attacks it, in the shape of the “ nigger” cater- 
pillars of the turnip saw-fly (Athalia spinarum), and the larvae 
of the white butterflies; these soon make skeletons of the 
leaves, and defile them by their excrements. Beneath the 
cuticles of the leaves the larvae of different kinds of two- 
winged flies excavate their winding tunnels ; other dipterous 
larvae riddle the turnip bulbs with innumerable mines, while 
the smother-fly, in two or three of its species (Ajohis), entirely 
destroys the leaves. Fat grubs — bad luck to them ! — the 
larvae of certain moths, bite off the young root, and sever it 
from the green portion ; wireworms, — i.e., the larvae of various 
click beetles (JElateridce) (all vermiform creeping things of the 
earth are wireworms in the farmer's zoology !), centipedes, 
and weevil beetles must be added to the long catalogue of 
turnip enemies. 
When we reflect on this formidable list of destructive 
agents in the form of insects, and add to it various fungi, 
which live parasitically upon the leaves (such as Peronospora 
parasitica, a species allied to the potato mould, and a kind of 
O'idium [ 'Erysiphe ] , which covers the leaves with its innumerable 
interlacements, looking like delicate threads of frosted silver 
under the microscope), it would seem almost to be a matter of 
* Some writers suppose that the Swede is the hybrid with turnip and 
rape. Professor Buckman (“ How to Grow Good Boots,” p. 15) says this is 
doubtless the origin. Has the point, however, I would ask, ever been satis- 
factorily established? 
