272 REPORT OF THE COMMISSIONER OF ACJRICULTURE. • 



serious annoyjojco, but also as bearing on the question of the migratory 

 l)Owers of the moth. We sliall have occasion to refer to this again. 



Although it a))pears from the letter of Dr. Ho.v that the moths injured 

 only those melons which were cracked, it is certain that in the case of 

 figs, (leaclies, and grapes the moths have the ])ower of piercing holes 

 through the unbroken rind of the fruit, and thus of destroying fruit pre- 

 viously uninjured. That a moth should have this ])o\ver is a remarkable 

 fact. As a rule, buttertlies and moths are only able to sip tlnid sweets 

 from open reservoirs, as the nectaries of tiowejs, the organ witb which 

 this is done being soft and flexible. 



AVhile i]i the field 1 ■ ;t year I carefull}" watched tlie operation of pierc- 

 ing the skin of a peach. At times the moth used the tip of its maxillae 

 as if it were trying to ])rick a hole into the fruit ; at other times the tip 

 of the maxillae was incurved, and the dorsal surface thus jiresented to 

 the peach used as a rasp. A study of the structure of the maxillae 

 shows how well axlapted they are for i)iercing and rasping. The tip 

 of the oigau is well adapted for ])iercing, as is shown by Plate IX, 

 Fig. 3; an<l the portion immediately ))receding the tip is equally well 

 adai>ted for rasjiing, being furnishe<l with numerous spines on the dor- 

 sal suriace. The ventral surface of this part of the organ is also i)ro- 

 vided with spines. Probably these are of little use in piercing the rind 

 of fruir, but doubtless they aid much in enlarging a hr.le when it is once 

 made, and also in lacerating the pulp of fruit, thus setting free the juice. 

 Plate IX, Fig. 4 represents a cross-section of the maxillae. The relation 

 of all the parts is well shown, excepting the arrangenumt of the Tuusoles 

 whicb are within the walls of each maxilla. These muscles were torn 

 in cutting the section.* 



There has been some discussion respecting the natural position of the 

 moth whOe at rest. I found that in the field it almost iuvariably alights 

 with its head down, but the majority of specimens which I saw in houses, 

 when resting on the walls, did so Avith the head directed upwards. 



During the warmer })art of the season the moths in con fmemeut began 

 to oviposit within thirty-six hours after emergijig from the pupa state. 

 Duiing the autumn the time varied from four days to a wes^k. The 

 greater number of eggs are laid during the night. As already stated, 

 the eggs are deposited chiefly on the lower surface of the larger leaves 

 on the niuldJe thiid of the plant. This may be oax ing to the fact that 

 the moth is attracted to that part of the plsmt by the nectar glands 

 whicli are on the leavi^s. In fact, Mr. Trelease ol>served moths alter- 

 nately sipping nectar ('ri)m these j^lands aiul ovipositing. During the 

 operation tlie moths flew irom leaf to leaf and from plant to plant, each 

 moth de])ositing Init a single egg on a leaf. Still, it we accept this as 

 explaining why the moths oviposit on that part of the plant, it is diffi- 

 cult to say why more eggs are not laid near the glands on the involucre, 

 which the moths also frequently visit. 



The number of eggs laid by a single moth ])robably varies from 400 

 to 600. September IJ, I counted the number of eggs in the ovaries of 

 a female taken in the field. There were 400 well-developed eggs and 



* As tLis report, is ■wiilten cliieflv for tliose wlio have not made a special study of en- 

 tomology, a few words in explanation of tlie structure of Ihe niajiillae of mollis wiU 

 not l)e out of place. In tbeir sirajtiest form, Ibe moulh parts of insects consist of au 

 upper lij), an under lip, and two pairs of jaws acting horizontally between them. In 

 the case of butterflies and moths (LrpidopUra) the lower pair of jaws (the maxillae) 

 is developed into two lout;, tiexible oigaus ; each of these bason one side a groove, 

 and the two are fastened together so thai the grooves lonn a tube, as shown iu tb« 

 ceu;erof I'^ii'. 4, PI. IX. 



