DB. T. DAVIDSON ON RECENT BRACIIIOPODA. 239 



setfc, dredged by ' Challenger ' Expedition between the Cape Verde Islands and Fernando 



Noronha, South America; much magnified. 21. Lower valve, dredged by the 'Valorous' 



Expedition, North Atlantic. 2.2. One of the barbed setje, much enlarged. 

 Figs. 23-26. D'lscbmra Cuyninr/i, Broderip. 23. Upper valve, nat. size. 23 a. Enlarged. 2i. Interior 



of lower valve, nat. size. 2o. The same, enlarged. 25 a. Exterior of upper valve, enlarged. 



All from St. Helena, and Panama, collected by 11. Cuming (Davidson Coll., Brit. Mus.). 



26. O. strigata, Broderip, after Broderip. 

 Figs. 27-30. Discmisca siella, Gould. 27, 20. Dredged by the ' Challenger ' Expedition in lat. 8° 56' S., 



long. 136° 5' E. ; off Bermuda (Brit, Mus.). 28, 29. Much enlarged. 30. A large example, 



after Reeve, nat. size. China Sens. (Cuming Coll., Brit. Museum.) 

 Figs. 31, 31 a. Discinisca antillarum, d'Orbigny. Cuba, INIartinique, much enlarged, after d'Orbigny. 



Plate XXVIl. 



Figs. 1-8. Crania anomala, Miiller. 1. Exterior of shell; Oban. 2. Interior of upper valve. 

 3. Interior of attached valve ; same locality (Davidson Coll., Brit. ]\Ius.). 3ff. Specimen 

 dredged by L. Barrett, Coast of Norway; enlarged. 4. Interior of a specimen in the 

 Jermyn-Strcet Museum, enlarged to show the labial appendages. 5. Vertical section of 

 shell of C. anomala, after Carpenter, showing its successive layers, traversed by vertical 

 channels, which present an arborescent division near the external surface, and a marked 

 contraction near the interior ; magnified 40 diameters. 6. External surface of shell (after 

 Carpenter) , showing the radiating arrangement of the subdivisions of its canals; magnified 100 

 diameters. 7, 8. Vertical sections of same, after King, showing that the vertical canals, on 

 approaching the dark-coloured or epidermal portion of the external layer, become minutely 

 subdivided into fi'om 2 to 5 branchlets, which appear like arborescent tufts. 



Figs. 9, 9 6. Crania anomala, var. alba, Jeffreys; Shetland. After Jeffreys's type. 



Figs. 10, 11. Crania japonica, A. Adams; Gotto, Japan (Davidson Coll., Brit. Mus.). 10. Natural 

 size. 10 a, 6. Exterior of upper valve, enlarged. 11. Interior, enlarged. 



Figs. 12,12a. Crania Poiirtalesi, Dall (C anomala''! var. Ponrtalesi, after Dall's figure); Sambos, 

 Florida. 



Fig. 13. Crania Suess'i, Reeve; Sydney, Australia (after Reeve) . (Cuming Coll., Brit. Mus.) 



Figs. 14-23. Crania turbinata, Vo\\,= Crania rostrata, Hoeninghaus. 14. Exterior of upper valve (after 

 Poll). 15, 15 6. A very conical example from the ]\Iediterranean Sea (Davidson Coll.). 16. 

 Interior of lower valve, from another Mediterranean specimen; natural size (Davidson Coll.). 

 17. Interior of attached valve, enlarged. 18. Interior of upper valve, enlarged. 19,20. Other 

 specimens from the same habitat (Davidson Collection, Brit. Mus.). 21. Crania rostrata, 

 Hoeninghaus's figure ; Mediterranean ; = C. turbinata. Poll. 22. Crania personata, after 

 Sowerby ; doubtless a malformed specimen of C. turbinata. 23. Another similar specimen ; 

 from the Mediterranean (Davidson Coll., Brit. Mus.). 



Plate XXVIII. 



Figs. 1, 1 a. Crania turbinata, var. ringens, after Hoeninghaus ; Mediterranean. 1 a. Enlarged. 



Figs. 2-4. Glottidia albida. Hinds. 2 & 4. Specimens from the Bay of Magdalena, California (Davidson 



Coll., Brit. Mus.) . 3. A larger example, after Reeve ; same habitat (Cuming Coll., Brit. 



Mus.). 

 SECOND SERIES. — ZOOLOGY, VOL. IV. 32 



