636 



ON SOME POLYZOA FROM THE LIAS. 



Stomatopora* sp. (PL XXY. fig. 10.) 



Zoarium adnate, dilated at point of attachment, flattened or very 

 convex. Zocecia uniserial, large and frequently of extraordinary 

 length (2 millim.), the free part then comprising two thirds of the 

 length of a single zocecium and springing from the point of adherence 

 at an angle of 45°, or, in some cases, almost vertically. The unat- 

 tached portion of the cell is also sinuous and coarsely wrinkled, and 

 though the surface-pores are throughout of the same type as in the 

 species already described, they are apparently fewer in number than 

 upon the adherent part. 



This form, so like a Stomatopora, is distinguished from any de- 

 scribed species of that genus by the greater length of the free parts 

 of the zocecia, and also by their size and the distance from peristome 

 to peristome. 



Horizon and Locality. From the Middle Lias, zone of Am- 

 monites spinatus. King's Sutton. 



Addendum [September 16, 1887]. 



The quarry from which these Polyzoa have been collected is 

 noted as having yielded many beautiful specimens of both Mollusca 

 and Corals, and amongst the rarer forms mention may be made of 

 Spiriferina oxygona, E. DesL, Pecten teoctorius, SchL, Mytilus avio- 

 thensis, Buv., Perna lugdunensis, Dumort., Phurotomaria mirabilis, 

 E. DesL, Thamnastrcea Etheridgii, Tomes, and Astrocamia, sp. 

 The Foraminifera are well represented, the examples of Dentalina, 

 Nodosaria, Margimdina, Vaginalina, and Cristellaria being excep- 

 tionally large, whilst species of Frondicularia, Glandulina, and other 

 genera occur also. An interesting addition to our fossil fauna is 

 made by the discovery of small forms of Calcispongias, which I have 

 submitted to so eminent a specialist as Dr. Hinde. He writes not 

 only that their condition is simply marvellous, but that they belong 

 probably to the existing group of the Leuconidse, examples of which 

 do not seem to have been found previously in a fossil condition. He 

 reserves their description for his forthcoming monograph. 



EXPLANATION OF PLATE XXV. 



Fig. 1. Tvhulvpora inconstans, sp. u., foliaceous form. X 12. 



2. The same, zocecium with closure. X 40. 



3. The same, worn zocecia showing surface-pores and subsidiary tubes. 



X45. 



4. The same, erect, SpiroporaASke form, showing ocecia. x20. 



5. The same, cylindrical form. x25. 



6. The same, showing fine threads upon the surface of the cells, x 25. 



7. The same, erect form, showing free proximal ends of zocecia. X 13. 



8. The same, flattened form of irregular growth, throwing off cylindrical 



branches, x 14. 



9. The same, showing ocecia. X30. 



10. Stomatopora, sp. X25. 



11. Species not determinable. X25. 



12. Tuhulipora inconstans, end of flattened lobe. X 30. 



* I have since found the same species in the Inferior Oolite of Dorset. Its 

 well-marked distinction from other forms will induce me to namo it Stomato- 

 pora elongata. 



