244 ENTOMOLOGICAL NEWS. [ J n ^Y ' T ^ 



WESFEI SCHEID, HEIXIUCH. 1912 Ueher die Biologic und Anatomic 



von Plea minutissima Leach. Zoologische Jahrbikher, Jena, 



XXXIII, p. 387. 

 WESENBERG-LUND, C. 1913. Fortpflanzungs-verhaltnisse ; Paarung 



und Eiablage der Siisswasserinsekten. Fortschritte der Naturwissen- 



schaftlichen Forschung, VIII, p. 195. 



EXPLANATION OF PLATES XIV AND XV. 



PLATE XIV. 



Fig. i. Ventral view of the genitalia of the female .V. irrorata show- 

 ing the drilling parts of the ovipositor indicated by V. It is 

 one of these parts that is figured from three aspects in Plate 

 XV, figure 9. 

 Fig. 2. A portion of water-soaked cattail leaf showing two eggs of 



A", irrorata deposited through one puncture. 



Fig. 3. Egg of A r . irrorata in Moneywort stem. The embryos usually 



develop with cephalic end at micropylar pole of the egg. This 



one is reversed as shown by the eyespot of the developing 



nymph within. 



Fiij. 4. Egg in Moneywort showing the nature of the rent through 



which the nymph escaped. Postnatal molt removed. 

 Fig. 5. Ventral view of the genitalia of the female N. insulata, show- 

 ing the drilling parts of the ovipositor indicated by V. It is 

 one of these parts that is figured from three aspects in Plate 

 XV, figure 5. 



PLATE XV. 



This plate contains three views of the left member of the first pair 

 of gonapophyses of the female of each of the species of the genus 

 Notonecta available in this country. Two species have been omitted 

 because of the lack of material. 



The views are from left to right : Outside or lateral view ven- 

 tral view showing the organ on edge Inner view. All of the draw- 

 ings were made with camera lucida and drawn to the same scale. The 

 length of the adult, together with outside measurements of the ovi- 

 positor are added for purposes of comparison of relative size of 

 parts. The writer believes that a study of these organs should be 

 taken into account in determining relationship of species. A study of 

 a wide series would certainly establish the range of variability in size 

 and shape of these parts and in some cases (if not all) aid in specific 

 determinations. The drawings here presented are, however, intended 

 to indicate merely the correlation of this organ with the habit of 

 oviposition. 



Fig. I. Notonecta lutca. Size of adult, 13-17.1 mm.; valve of ovi- 

 positor. 1.025 mm. \ .725 mm. Specimen loaned by Mr. Gib- 

 son, of Nat. 'Mus. Taken in Finland by Sahlberg and determined 

 by Kirkaldy. 



