PLATE XXIV 

 BRACHIA (Pagk 293) 



FiGUUE 1. —Brachial supports of Macaiulreria cranium ]\Iiillor; nearly 

 adult; p, p, points of former attachment to a septum in terehrataliform 

 stage. Enlarged. 



Figure 2. — Dorsal valve of Terehrntulina septentr'wnalis Conthouy, 

 with cirrated brachia attached ; showing relations of calcareous loop, 

 which is darkly shaded in the drawing. 



FiGUUE 3. — Dorsal valve of Maciellania kerguelenensis Davidson, with 

 cirrated brachia attached ; showing relations of calcareous loop, wliich is 

 darkly shaded in the drawing. 



TEREBRATALIA OBSOLETA Dall (Pages 406-408) 



Figure 4. — Eoop in late platidifonn stage, with cirrated margin of 

 lophophore attached. X 15. 



Figures. — Side view of lower half of preceding; showing cirrated 

 edge of lophophore passing from the descending branch of loop to sep- 

 tum, and over ascending branch. X 15. 



Figure 6. — Dorsal view of adult shell. Natural size. 



Figure 7. — Exterior of ventral valve. Natural size. 



Figure 8. — Profile ; sliowing relative convexity of valves. Natural 

 size. 



Figure 9. — Front view. Natural size. 



Figure 10. — Early larval brachiopod ; interior of dorsal valve ; show- 

 ing the incomplete circlet of tentacles or cirri, visceral mass, and some of 

 the muscles ; ti, l\', first tentacles developed ; <2, ^a', second pair of ten- 

 tacles ; /3, U', third pair of tentacles; U, W, last pair; /5, new tentacle 

 just growing on one side of median line; m, mouth ; <l.f, dental sockets; 

 did, diductor muscles; ad, adductor muscles. X 90. 



Figures 10, 11, 12, are drawn from specimens which had been dried 

 and afterward expanded by soaking in water, and tlien stained and pre- 

 pared for mounting. The original proportions and relations of jiarts 

 may be therefore somewhat altered. 



Figure 11. — Gwyniform stage; showing complete circle of cirri ; ps, 

 pallial sinus ; se, seta; in edge of shrunken mantle. X 60. 



Figure 12. — Cistelliform stage; showing deflection of growing cir- 

 rated edge of lophophore by dorsal septum (.s) ; m, mouth ; ad, adductor 

 muscles ; did, diductor muscles ; ds, dental sockets. X 60. 



