442 DISCOVERY REPORTS 



4. Round-headed avicularia with long down-turned beak, large long-headed avicularia 



sinuous dorsally (i.e. with concavity at beginning of beak) ... ... 7. C. giganteus 



Round-headed avicularia with small down-turned beak, large long-headed avicularia 



convex or straight dorsally 1 ... ... ... ... ... ... 6. C. lewaldi 



5. Avicularia all alike, branches biserial ... ... ... ... ... 9. C. abyssicolus 



Avicularia of two kinds, main branches with more than two series of zooecia ... ... 6 



6. Three strong spines (of which one is median) on each non-fertile zooecium, large avicularia 



with pointed posterior process on each side, axillary secondary branches exceptional 



8. C. tricornis 

 Spines not median, avicularia without pointed processes, axillary secondary branches 



common ... ... ... ... ... ... ... ... ... 10. C. angustus 



7. Axillary rootlets adhering to basal surface of branch, outer distal corner of zooecium 



turning forwards ... ... ... ... ... ... ... ... 19. C. lunatus 



Axillary rootlets not adhering to basal surface, outer distal corner not turning forward 



(though spine may) ... ... ... ... ... ... ... ... ... ... 8 



8. Cryptocyst present, zoarium biserial and jointed, lateral rootlet-chamber without runner ... 9 

 Cryptocyst absent, zoarium biserial or pluriserial, unjointed, lateral rootlet-chamber with 



runner ... ... ... ... ... ... ... ... ... ... ... 10 



9. Axillary rootlet issues frontally and symmetrically, internal projection from basal wall of 



zooecium present, opesia usually short ... ... ... ... ... 20. C. areolatus 



Axillary rootlet issues basally and asymmetrically, no internal projection from basal wall, 



opesia usually long ... ... ... ... ... ... ... 21. C. asymmetricus 



10. Zoarium biserial, sometimes triserial in part, a single distal spine originating from basal 



surface of outer corner of some zooecia ... ... ... ... 18. C. reticulatus 



Zoarium pluriserial, spines, when present, on either or both of the distal corners, not basal 1 1 



11. Zooecia very long, narrow, straight-sided, axillary rootlets issuing from frontal surface of 



chamber ... ... ... ... ... ... ... ... 17. C. rectilinearis 



Zooecia not very long, narrow or straight-sided, axillary rootlets issuing from basal surface 



of chamber ... ... ... ... ... ... ... ... ... ... ... 12 



12. Spines present, avicularia of two kinds, large and small, ovicells radially striated at first, 



with additional sculpture later ... ... ... ... ... ... ... ... 13 



Spines absent, avicularia all small, ovicells radially striated or fluted, without additional 



sculpture 16. C. atlanticus 



13. Spines directed frontally, zooecia not raised distally, large avicularia with long stalks, small 



avicularia very variable in size, their lower head-angle about 90 ... ... ... 14 



Spines, with few exceptions, directed distally, zooecia somewhat raised distally, large avicu- 

 laria short-stalked, small avicularia not very variable in size, their lower head-angle acute 1 5 



14. Fully calcified ovicells rather heavily reticulate, some, at least, of the meshes more or less 



hexagonal, fertile zooecia with one or both spines long and stout ... 11. C. retiformis 

 Fully calcified ovicells with light, irregular reticulation, not forming hexagonal meshes, 



spines on fertile zooecia not enlarged 12. C. retiformis var. tenuispina 



1 5 . Fully calcified ovicell sparsely punctate, large avicularia not on marginal zooecia 13. C. latus 

 Fully calcified ovicell not punctate, large avicularia usually on marginal zooecia ... ... 16 



16. Fully calcified ovicell radially striated, not thickened or roughened, reticulation, if any, 



faint, spines directed distally, large avicularia round-backed ... 14. C. latus var. striata 

 Fully calcified ovicell thickened and roughened after a distinct reticulate phase, spines 

 variable directed distally or obliquely forward, large avicularia flat-backed 



15. C. latus var. aspera 

 1 One specimen had a second type of large long-headed avicularium. 



