120 



Anterior Subcostal Basivenale oriented distad; broadly ovoid; convex; moderately elevated 

 dorsad. Proximal and distal sections separated by a prominent suture. Proximal section 

 strongly and extremely broadly extended anteriorly and postero-proximally as a very broad 

 convexity; much larger than the distal section. Distal section discontinuous with the ScA 

 bulge; separated by a moderately deep concavity. Apex broadly rounded; oriented distad. 



- Subcosta Anterior moderately convex; moderately extended posteriad. Bulge moderately 

 broad. 



Radial Basivenale convex; open; discontinuous with radial stem; angled proximad; 

 rectangular. Proximal arch slenderly deltoid; curved postero-distad. Anterior section 

 strikingly reduced by a greatly enlarged br; discontinuous with the anterior margin of BR. 

 Posterior margin weakly concave; surrounds the BMA arch apex. Postero-distal margin 

 truncate. Anterior margin depressed below the posterior margin of ScA bulge; moderately 

 broad; straight; angled proximad. Embayment normal size. Distal arch discontinuous with 

 radial stem; moderately broad; convex; broadly curved proximad; oriented postero- 

 proximad. br strongly sclerotized; occupies about one-third of the proximal arch; 

 discontinuous with BR. br projection slender; short; concave; weakly distinct from BScA. 



Second Basal Plate (Fig. 197) 



MA-BMA Junction absent. - MP-BMP Junction: MP broadly continuous with BMP; arises 

 from below the BMP-BCuA brace. - Crimp Patterns absent. - BMP-CuA Brace absent. 



- BMP-BCuA Brace present but modified; discontinuous with BMP; entire and greatly 

 strengthened; extends posteriad; posteriorly enlarged; convex; distinct from BMP. 

 Terminus fused to a deep concavity on the disto-medial section of BCuA. Point of fusion 

 discontinuous. 



Medial Basivenalia reduced proximally. BMA broadly scaphoid; completely fused to BMP. 

 Proximal surface convex. Medial and distal surfaces planate. Anterior margin concave. 

 Proximal arch very short; planate and straight; oriented antero-proximad; strongly curved 

 ventrad. Apex terminates below BR proximal arch apex. Distal arch indistinct; fused to 

 the proximal section of BMP. BMP junction with BMA discontinuous and very broad; 

 fused to brace; markedly convex; separated from both IBP and BCu by membrane. 

 Proximal section broadly deltoid; planate; slopes ventro-distad. Distal section 

 indistinguishable from BMP-BCuA brace; long; broad; rectangular; strongly convex. 

 Cubital Basivenalia broadly fused. Posterior margin of BCuA fused with the anterior 

 margin of BCuP Suture line present. BCuA very narrow and long; convex; oriented distad; 

 lies posteriad of BMP; strongly sclerotized. Anterior margin with an extremely broad 

 extremely deep concavity. Distal margin continuous with CuA. BCuP weakly deltoid; 

 convex; oriented posteriad; moderately sclerotized. Distal embayment very narrow but 

 deep. - Cubitus Anterior fused to BCuA. Junction indistinct. 



Basalare (Fig. 198) 



Head - HP lobe large; continuous with neck. Apex broadly truncate. Dorsal surface weakly 

 elevated from neck; not polished. BScP lobe claviform; weakly projects posteriad from 

 neck. Dorsal surface rectangular; weakly convex; polished; depressed from neck; slopes 



