Platk 18. 



I''i(;s. l-!>. S<-lii.:(jitliosccn>i iiitcrsl iliii l.e:\. ^y.','^ (p. i'<-'\). 



1. Six zoMi'ia. iiiiturnl sizp. 



2. Ti'Mii.sverse fracture of :i Z(i;iiiuiii, X -H. The pores of the base are prolonged 



into tubules. 

 .3. Anoestrular portion of a zoariiuii, X 2(), with numerous heterozooeoia. 



4. Inner side of a zoariuni. X 20. sliowinj; Uie ancestrula at the center and aviciili'ria 



with bar uoar liy. 



5. Another view of tlie ancestrula as shown on the inner side. X 20. where simple 



cavities surrouud the ancestrula. 

 0. Portion of outer side of zoarium, X 20. showing several large niemlirani]ioroid 

 zooecia. 



7. Cenlral portion of the exterior of a zoarium. X 20. The ancestrul,-i is siu'ronndod 



by radicular zooeci.a. 



8. An example, X G. 



0. Portion of zoarium, X 20. willi ovirelle<l zooecia. 

 Claiboriiian (Gosport sand): Clailiorne. Alaliania. 

 Cat. No. 62809, U S.N.M. 

 Flos. 1(1—1.7). .s'c/M':o/7/io.vcro.< indiKliinn'oxiiiii. new sjiecies (p. 027 1. 



10. Two zoaria, natural size. 



11. Portion of a zoariuni, X 20. showing distinctness of zooecia exteriorly. 



12. Tangential thin section, X 20. 



13. Celluliferous outer face. X 20, illustrating the zooecia and the separating zooeciules. 

 14, l."i. Basal side of a zoarium. X ti, and X 2(». 'J'ho zooeci.i are indislim/t. but each is 



marked by one large and one small jiore. 

 Claibornian (Gosport sand) : Claiborne, Alabama. 

 Cat. No. C3803. T'.S.N.M. 

 Fios. ir>-10. Sc!ii:orthoscc(tf^ nididliiin, new siiecies (ii. 02.S). 

 10. Two examples, natural size. 

 17. 18. Two zoaria, X 20. The lateral .-ivicularia .-ind the i-ostules of the zooecial frontal are 

 indicated. 

 19. Inner side of a zoarium. X 20. exhibiting the characteristic radiating ribs. 

 Cl.-iibornian ((iosport sand): Claibome, Alabama. 

 Cat. Xo. 6.3804, TT.S.N.M. 



19 



