Oct.. 1914-Mar.. 191S 



Illustrations ix 



Page. 



Plate XXXIX. Fig. i. — Leaf showing work of four Agrilus beetles in 24 hours. 

 Fig. 2. — Hole in bark made by adult Agrilus in emerging from pupal cell. 

 Fig. 3.— Larvae of Agrilus bilineatus and their burrows. Fig. 4. — Complete 

 burrow of a larva of Agrilus bilineatus. A, Point at which larva hatched; 

 B, beginning of second instar; C, beginning of third instar; D, beginning 

 of fourth instar; E, pupal cell 294 



Susceptibility of Citrous Fruits to the Attack of the Mediter- 

 ranean Fruit Fly 



Plate XL. Fig. i. — Orange infested with larvse of the Mediterranean fruit fly 

 (Ceraiitis capitata). Fig. 2. — Orange infested with larvae of the Mediter- 

 ranean fruit fly {Ceraiitis capitata) , showing two breathing holes of the larvae 

 in the decayed area 330 



Plate XLI. Cross section of shaddock No. i, showing the thick, loose texture 

 of the rag with darkened area above and to the right showing the channels 

 made by well-grown Mediterranean fruit-fly larvae 330 



Plate XLII. Fig. i. — Cross section of the orange shown on Plate XL, figitfe 2. 



Fig. 2. — Orange containing 87 punctures in the rind 330 



Three-Cornered Alfalfa Hopper 



Plate XLIII. Fig. I. — The three-cornered alfalfa hopper (S/!c/oce/)/!a/a/«<jna): 

 Adult, o. View from side; 6, view from front. Fig. 2. — The three-cornered 

 alfalfa hopper: a. Nymph in first stage; b, egg. Fig. 3. — The three-cor- 

 nered alfalfa hopper: Nymph in second stage. Fig. 4. — The three-cornered 

 alfalfa hopper: Nymph in third stage. Fig. 5. — The three-cornered alfalfa 

 hopper: Nymph in fourth stage. Fig. 6. — The three-cornered alfalfa hop- 

 per: Nymph in fifth stage. Fig. 7. — An alfalfa stem showing feeding punc- 

 tures of the three-cornered alfalfa hopper: a. Ring or girdle of punctiures 

 around the stem; b, gall resulting from girdling 362 



Life History of the Mediterranean Fruit Fly from the Stand- 

 point OF Parasite Introduction 



Plate XLIV. Fig. i. — Wooden boxes, 14 by 12 by 3 inches in size, used in 

 obtaining pupa? of fruit flies. Fig. 2. — Contrivance used for keeping the 

 infested fruit free from the sand and bringing the emerging larvae to a 

 central container where they may be gathered quickly 374 



Plate XLV. Fig. i. — Method of keeping adult fruit flies alive over long periods. 

 Fig. 2. — An apple after having been suspended for one day in a jar con- 

 taining Mediterranean fruit flies 374 



Relation op Simultaneous Ovulation to the Production ok 

 Double- YoLKED Eggs 



Plate XLVI. — Fig. i. — Large yolk (weight, 30.12 gm.) with two germ disks; 

 found in a large hen's egg. Fig. 2. — Fused immature yolks (weight, 1.45 

 gm.); found in a small hen's egg. Fig. 3. — Type I double-yolkcd egg, 

 showing two yolks with separate vitelline membranes but inclosed in a 

 common chalazif erous layer 386 



Plate XLVII. Fig. i. — Type I double-yolked egg, showing two yolks with sep- 

 arate vitelline membranes but inclosed in a common chalaziferous layer. 

 Fig. 2. — Type II double-yolkcd egg, showing two yolks with separate cha- 

 lazal membranes but common thick albumen 386 



