1920 



AMERICAN BEE JOURNAL 



87 



fasten the end as usual, and then 

 drive in the nail in the top-bar to 

 tighten the wire. Before wrapping 

 the third wire around the nail I take 

 out as much slack as possible in 

 wires No. 1 and 2. 



This gives a wire at the bottom to 

 prevent buckling of the foundation. 

 At the same time I obtain the advan- 

 tage of the points of contact of the 

 crossed wires. This method is nearly 

 as rapid as the usual one. and the im- 

 bedding of the foundation can be 

 done with bell transformer on the 

 lighting circuit or with an electric 

 iron circuit. 



A. MESERVE. 



Honeydew 



By Ale.x. D. MacGillivray 



THE thin, clear, sweetish, glutin- 

 ous substance extracted in dew- 

 like drops by certain insects is 

 known as honeydew. It is extruded 

 from the rectum of the insect through 

 the anus and is considered as the ex- 

 cretion of the insect. That this ex- 

 cretion is entirely excreta is open to 

 question. 



The early students of plants and 

 animals diflfered decidedly as to the 

 origin of honeydew. The botanists 

 put forth arguments that seemed to 

 show absolutely that this watery sub- 

 stance found upon the upper surface 

 of leaves during the summer was 

 excreted by the plant. The argument 

 was supported by such eminent sci- 

 entists as Liebig and Hooker. Even 

 some entomologists thought it was 

 excreted by the plant. The argu- 

 ments of these workers were based 

 upon theoretical considerations and 

 it was impossible for such arguments 

 to overcome conclusions based upon 

 actual observation. For many stu- 

 dents of insects, even as early as the 

 time of De Geer (1778), had observed 

 the actual passage of the bubble-like 

 drops from the anal opening of dif- 

 ferent species of plant lice. The in- 

 sect origin of honeydew has been 

 confirmed so many times that it 

 is now an accepted fact. The ordi- 

 nary observer, if he so desires, can 

 readily demonstrate its origin during 



the summer months by observing 

 some plant lice under a lens giving a 

 slight magnification. The fact must 

 not be overlooked that certain plants 

 do exude substances, but they are al- 

 ways of a very different character, 

 usually thicker and more opaque than 

 honeydew. 



The insects that produce honeydew 

 belong to the order Hemiptera. To 

 this order belong the insects which 

 the entomologist designates as bugs, 

 or true bugs. Some of the more com- 

 mon are the bedbug, the stinkbugs, 

 which give the acrid taste to berries, 

 the seventeen-year locust, aphids or 

 plant lice, and scale injects. All the 

 insects included in this order are 

 sucking insects. Their food is either 

 the blood of animals, as with the bed- 

 bugs, or the sap of plants, as with 

 the plant lice. Their mouth parts, 

 because of their sucking habits, are 

 greatly changed from those of a cat- 

 erpillar or a grasshopper, which are 

 for biting. The lower lip is modified 

 into a comparatively long cylindrical 

 projection, the rostrum, which con- 

 sists of three or four segments. It 

 also has a deep furrow on the upper 

 side. The sides of this furrow are us- 

 ually adjacent, forming a tube which 

 can be opened on one side or held se- 

 curely closed at the will of the insect. 

 The two pairs of jaws are modified 

 into four long bristle-like structures. 

 These are extruded through the 

 mouth and through the furrow in the 

 rostrum. The bristle-like mouth 

 parts are longitudinally furrowed and 

 firmly folded together so as to form 

 a slender tube with an extremely fine 

 lumen, much smaller than the lumen 

 in the needle of an ordinary hypoder- 

 mic syringe. These closely folded 

 bristles, which are about as long as 

 the body, or four or five times its 

 length, are known as the rostralis. 



When the insect gets ready to draw 

 up sap, the rostrum is held at right 

 angles to the body and the bark of 

 the plant, and serves as a support for 

 the rostralis, which extends through 

 its central furrow. The free end of 

 the rostralis is sharp and with the 

 support given by the rostrum, the in- 

 sect is able to puncture the bark of 

 the plant and force the rostralis into 



Bees in English hives in China. 



the tissues of the plant where there is 

 an abundant supply of sap. Located 

 in the head and associated with the 

 rostralis, there is an efficient pump. 

 This makes it possible, once the in- 

 sect has its rostralis fixed in the tis- 

 sues of the plant, to pump the sap 

 into its pharynx, where it is mixed 

 with the excretions from the salivary 

 glands and digestion is begun. The 

 great length of the rostralis in many 

 insects of this group is probably to 

 permit slight movements of the in- 

 sect without disconnecting it from 

 the plant or breaking off the end of 

 the rostralis in the tissues of the 

 plant. 



The number of families of Hemip- 

 tera, of which the species produce 

 honeydew, is not large, only six. 



1. The family Membracidae, the 

 Tree hoppers or Brownie bugs, in- 

 clude only a few species which pro- 

 duce honeydew, and these produce 

 only a small amount. The abdomen is 

 elongated, the posterior portion is 

 tubular and the anus is located at the 

 free end of the tube. 



2. The family Cercopidae, the Frog- 

 hoppers or Spittle insects, includes 

 species all of which produce honey- 

 dew. It is said of some of the exotic 

 species that five or six dozen individ- 

 uals, will produce a quart in an hour 

 and a half. They are the insects that 

 produce the small, frothy or spittle- 

 like masses in the angles of plants. If 

 this mass, which is honeydew mixed 

 with air, is pushed aside, an insect 

 will be found. The froth is produced 

 by the insect keeping its abdomen in 

 motion and mixing small air bubbles 

 with its honeydew as it is excreted. 



3. The family Psyllidae, the Jump- 

 ing plant lice, often produces great 

 quantities of honeydew. Slingerland, 

 in writing of the pear tree Psylla, 

 says: "It literally rained from the 

 trees upon the vegetation beneath; 

 in cultivating the orchard the backs 

 of the horses and the harness often 

 became covered with the sticky sub- 

 stance dropping from the trees. It 

 attracts thousands of ants, bees and 

 wasps, which feed upon it." 



4. The family Alcyrodidae, the 

 White flies, are mainly tropical or 

 sub-tropical species, and in these re- 

 gions produce great quantities of 

 honeydew. The species found in tem- 

 perate regions, while numerous in 

 species, are rarelj' numerous in num- 

 ber of individuals, and do not produce 

 a large quantity of honeydew. 



5. The family Coccidae, the Scale 

 insects, Mealy bugs, or Coccids, are 

 likewise more abundant in tropical 

 and sub-tropical regions, where the 

 species of certain groups produce 

 enormous quantities of honeydew. It 

 is from this that much of the inferior 

 grades of imported honey are pro- 

 duced. Some of the species of Coc- 

 cids found in temperate regions pro- 

 duce large quantities of honeydew 

 just prior to or at the time they are 

 producing eggs or giving birth to 

 young. In the Coccidae all the honey- 

 dew is produced by the females, 

 young and adults. Such species as 

 the San Jose scale or the oyster shell 

 scale do not produce honeydew. It 



