it bears small coremata or membraneous sacs covered with 

 hairs (Gymnoscelis pumilata, pi. xxxii.). In the AcidaliincB 

 the coremata consist of .pencils of long hairs (pi. xxi). I 

 give further details of this segment under the next heading. 



THE TEGUMEN. Buchanan White. 

 The base of the tegumen rests in the plane of the 

 ventral surface, whilst the upper part curves anally until 

 it lies longitudinally in the plane of the dorsal surface. 

 It may perhaps be best described as a complete ring of 

 chitine, dorsally broad, ventrally narrow, with much 

 strengthened edges, and it is articulated laterally in the 

 middle, enabling the upper half to be thrown backwards 

 towards the head. The penis and its armature are con- 

 nected at this articulation. 



THE SACCUS. Bethune Baker. 

 The basal portion of the tegumen, which I called the 

 Vinculuin in the "Noctuidae," had already been named The 

 Saccus by G. Bethune Baker (Trans. Ent. Soc. London, 

 1891), and this latter name I accordingly now adopt. Its 

 form is generally that of a pouch or bag, but in some species 

 it is incomplete, the two sides of the tegumen failing to 

 meet (Deuteronomos erosaria, pi. mi.). 



THE VALV^E. Burmeister. 



Below the articulation of the tegumen on either side 

 is hinged a lateral flange which was called the Harpe in 

 the "Noctuidse." I now adopt the name of Valva used pre- 

 viously by Burmeister. Kambur, in 1838, employed the 

 word pinces. In the Geometridce the valva is often simple, 

 but occasionally possesses a spiny armature, by no means 

 as constant in form in this family as in the Noctuidce. I 

 have therefore united the parts of this armature, where it 

 occurred, under Gosse's name, The Harpe. The valva 

 may be divided into three parts, which are usually more or 

 less fused together, but are sometimes separated and free. 



