80 
THE CURCULIO. 
THE CURCULIO. 
The Curculio, (Rhynchcenus Ccrasi , Peck,) its natural 
history, habits, character, and the best mode of pre¬ 
venting: its destructive ravages; together with re¬ 
marks on the cause of the disease known as the 
Warty Excrescence, and suggestions to prevent its 
appearance. In a letter to the Committee on Fruits 
of the Massachusetts Horticultural Society. By 
Dr. Joel Burnett, Southborough, Mass. 
This insect was called by Herbst, Rhynchcenus 
Nenuphar: by Peck, Rhynchcenus Cerasi — but 
commonly goes by the name of curculio , or plum- 
weevil, by horticulturists. “ He is a little rough, 
dark-brown beetle, has two small bunches or pro¬ 
tuberances on his back, a rostrum or beak on 
which are two antennse. 
(Fig. 11.) 
The Curculio of the natural sjze. 
He is so shy and retiring and unobtrusive in his 
character, in his beetle-stage, that he is not liable 
to be seen unless he is searched-fbr purposely, and 
this is the reason why so little is known of him 
generally. 
When you have discovered that he is operating 
upon the fruit, which you may know by his pe¬ 
culiar mark upon it, by as¬ 
siduously watching, you may 
chance to see him cutting the 
incision with his rostrum, 
(Jig. 12.) If you extend 
your thumb and finger toward 
him, it must be done very 
cautiously and slily, or before 
you touch him he will drop, 
as imperceptibly as a small 
shot would, to the ground. 
It should be remarked, that 
we do not know that he uses 
the fruit for his food, but 
chooses it as receptacles for 
The Curculio in the act his eggs. 
Of making the semi-iu- He begins his work upon 
nar incision with his . . ° •, . 1 
rostrum, or beak. the plum and apricot, as soon 
in the season as the small 
cap or covering, formed by the blossom, falls off, 
but not so soon upon the peach. Examining the 
fruit occasionally or daily, you are to know when 
he has commenced his work by his peculiar mark 
or incision, which is readily seen on fruit with 
smooth skin, as the plum, cherry, apple, &c., but 
on the peach it is known by a small drop of gum 
oozing from its surface. It has been stated that 
the furzy surface on the peach, is a barrier or ob¬ 
stacle in his way, but it does not prove so here, as 
the injury which it sustains is quite general, unless 
protected. 
I say, then, he is known to be on the fruit-tree 
by his peculiar mark on the fruit. This mark is 
the wound he makes with his rostrum, which 
consists in raising up the skin of the plum to a 
small extent, under which he deposites an egg. 
The shape or form of this mark is semi-lunar or 
crescent-shape, and in the middle of this wound 
is a small discolored speck, where the egg is 
placed, (figs. 13, 14, 15.) 
In the early part of the 
season,or during the month 
of June, his mark will be 
found near the apex, or 
point of the plum (fig. 13.) 
But after the plum has 
reached aconsiderablesize, 
or from the 1st to the 20tfi 
of July, his mark will be 
found at the base, or near 
where the stem is insert* 
ed, (fig. 14.) 
This last-mentioned place 
the insect prefers, it would 
seem, from instinct, lest 
the plum, by its strong 
connexion to the tree, 
should not fall soon enough 
to secure the welfare of 
the grub within it; for this 
vital connexion is sooner 
disturbed by the worm 
than it would be if the egg 
had been deposited at the 
apex. 
When the egg hatches, 
the larva sometimes, it is 
presumed, falls from the nidus or nest, and the 
fruit remains unharmed; but most generally, in 
(Fig. 15.) (Fig. 15.) 
Fig. 14 shows the incision near the base, in large plums. Th© 
small or discolored spot, at the inner line of the mark, Is the 
nest where the egg lies. 
Fig. 15 shows the blue line, which indicates that the grub is 
eating within. 
four or five days from the time the egg is laid, 
a small bluish line, near the skin, may be seen 
extending from his mark, (fig. 15,) which signi¬ 
fies that the grub is within. And also when his 
mark has assumed a bluish tint, you may be cer¬ 
tain that destruction will follow; for when you 
(Fig. 12.) 
(Fig. 13.) 
Incision near the apex in 
small plums. 
