On Ileterocera from Costa Rica. 577 



In 1904 (Trans. Zool. Soc. xvii. pt. 3) I arranged the 

 genera in five subfamilies ; these may be grouped as 

 follows : — ^ 



I. Pliaryngeals toothless ; liasuial spines not bifid ; supra-cleitliral 



plate extending downwards, its inner surface attaclied to the 

 outer edge of the cleithrum, but not forming a definite articulation 

 ■with it ; body usually armoured ; • inner edge of metapterygoid 

 attached to lateral ethmoid ; hypocoracoids interlocking. 



Plecostomince, IIi/2)opf.opo7natin(S, 



II. Lower and fourth upper pharyngeals toothed ; anterior hajmal 



spines bifid for reception of anal basalia ; supra-clelthral plate 

 scarcely decurved, its lower surface with a transverse ridge fitting 

 a groove on the upper edge of tlie supra-cleithral expansion 

 external to the head of the bone. 

 Body armoured ; metapterygoid attached to 

 lateral ethmoid ; lower portions of cleithra 

 transverse ; hypocoracoids interlocking 



below Loricariince, Neopleco- 



stomince. 

 Body naked ; metapterygoid small, not reaching 

 skull ; cleithra running somewhat forward 

 to their symphysis ; hypocoracoids taper- 

 ing forward below, not interlocking .... Argiince. 



It seems to me that if the Argiidse are to be separated off 

 as a distinct family, the Plecostomidaj also should be recog- 

 nized, as they differ quite as much from tiie Loricariidae. 



LXVI. — New Species of Heterocerafrom Costa Rica. — XI. 

 By W. SCHAUS, F.Z.S. 



Geometridae. 

 Aplogompha argeniilinea, sp. n. 



cJ . Palpi andfions hlacine buff; vertex, collar, and tliorax 

 dull lilacine brown ; abdomen dark brown above, silvery 

 grey below. Fore wings : the basal half to middle of costa 

 and postmedial line on inner margin black-brown, crossed by 

 some buff striae, and containing a few metallic scales in cell 

 outwardly, followed by a large triangular whitish spac3 

 shaded with fuscous scales and with its apex at vein 2, its 

 costal area shaded with buff; a postmedial dark reddisli- 

 brown line, followed by fine buff and dark brown lines, and 

 a heavy silvery line outwardly shaded with black and not 

 reaching costa ; a dull buff-grey space beyond the silver line 

 limited by a straight subtermiual white line, beyond vvhich 



