SUBFAMILY LECANIINAE 163 



caudal end of the ventral thickening. These setae are the sub- 

 apical setae. While there is frequently two subapical setae, there 

 may be as many as five or more. The small setae, generally if not 

 always four in number, located caudad of the subapical setae are 

 the apical setae. They may be located on the dorsal aspect or on 

 the ventral aspect or a part of them may be located on the dorsal 

 and the remainder on the ventral aspect. At times some may be 

 located on the margin of the operculum. The caudal half of the 

 dorsal surface in certain species bears a single large seta, the 

 discal seta. This seta is of about the same size as the subapical 

 setae and is located on the same portion of the dorsal aspect of the 

 operculum, so that in mounted transparent specimens, they appear 

 to be closely associated. 



The ventral aspect of the body cephalad of the opercula bears 

 a series of three or more pairs of small setae, the abdominal setae 

 of Green. These setae are usually arranged in two longitudinal 

 rows. The ventral aspect of the abdomen cephalad and laterad of 

 the opercula also bears a few scattered cerores, the circumgenital 

 glands of Green. 



The cuticle of the dorsal aspect of certain lecaniids, as the 

 species of the typical genus and its allies, when studied under 

 transmitted light, show a more or less distinct pattern of variously 

 shaped areas. These areas are usually round or oval or suboval 

 and appear as large cellular areas. They frequently consist of a 

 series of concentric lighter and darker colored bands or areas and 

 are known as the cells or as the dermal cells or pores or cellulae. 

 They are not cells in a histological sense but are probably thicken- 

 ings of the cuticle of different density. They vary greatly in 

 number, shape, and size in the different species. The cellulae are 

 more distinct in old individuals, they also become indistinct after 

 a long boiling in caustic potash. Those species, where the cellulae 

 form a series of disconnected rings or ovals, are said to have the 

 cuticle alveolate. When these areas are connected forming a 

 series of adjacent polygonal areas, these areas are designated as 

 tesserae. 



The opening in each cellula is, so far is observed, always the 

 mouth of a ceratuba or an oraceratuba. The oraceratubae are 

 usually, if not always, eccentric in position. The ceratubae appear 

 to be characteristic in form but vary greatly in length. Each 

 generally consists of a proximal straight tube bearing a smaller 

 curved portion or tube. The change in diameter of the two tubes 



