152 



THE ENTOMOLOGIST. 



themselves that this Danish zoologist has contributed his latest three 

 or four fine monographic memoirs upon the Arthropoda in their 

 language. 



Pihijnckuta. — T. Pergande works out very fully the interesting and 

 complex life-histories of HonHnphis hanuonelidis and Hcwicimelistes 

 spinosns (1901, " The Life-history of Two Species of Plant-Lice," 

 U.S. Dep. Agric, Entom., Techn. ser. 9, pp. 1-44; 23 text figs.). 



Lt'pidoptera. — H. Gadeau de Kerville discusses tlie copulation of 

 Lepidoptera (" L'accouplement des Lepidopteres," 1901, Bull. Soc. 

 Ent. France, pp. 76-81 ; 5 figs.). 



Coleoptera. — -The variability of the two-spot ladybird is considered 

 by C. Schroder (" Die Variabilitat der Adalia bipunctata, L., gleich- 

 zeitig ein Beitrag zur Descendenz-Theorie "; Illustr. Zeitschr. Entom. 

 1901, No. 24 ; 1902, Nos. 1 to 5 ; 1 plate and 5 text figs.). 



G. W. K. 



J. H. CoMSTocK AND Chujiro Kochi, " The Skeleton of the Head of 



Insects." 1902. 'American Naturalist,' xxxvi., pp. 13-45; 



29 text figs. 



The skeleton of the head, particularly in the more generalized 



forms, is discussed at some length. The authors consider that the 



existing nomenclature is "really of little morphological value; for 



but few of the primitive sclerites of the head have remained distinct, 



and some of them greatly overshadowed others in their development. 



The result is that in some cases a named area includes several 



sclerites, while in others only a portion of a sclerite is included." It 



is maintained that seven segments exist, with the following sclerites 



and appendages. " In each section of the middle column the dotted 



line indicates the division between the sternal and lateral elements of 



the segment." 



SEGMENTS. SCLEEITES. APPENDAGES. 



1. Ocular (Protocerebral). Vertex and genae. 



Ocular sclerites. 



Front. 



2. Antennal (Deuterooerebral).Antennal sclerites. 



Antennae. 



Clypeus proper. 



3. 2nd Antennal (Tritocerebral) 2nd antennae of Campo- 



Labrum (Mouth). dea et al. 



4. Mandibular. Postgenal. 



Mandibles. 



Antecoxal pieces. Trochantin (of do.). 



Pharyngeal sclerites. 



5. Superlingual. Superlinguse. 



6. Maxillary. Maxillary pleurites. 



Maxillffi. 



Lingua. 



7. Labial. Dorsal cervical sclerites. 



Lateral do. do. 



Labium. 



Ventral do. (Gula). 



G. W. K. 



Erratum. — Page 16, line 4, for "prolegs " read " forelegs." 



