CONTRIBUTION TO THE PALEONTOLOGY OF TRINIDAD. 105 



merited only by faint lines of growth and very delicate, microscopic, radiating 

 striae, otherwise entirely smooth; convexity of dorsal and ventral valves nearly 

 equal. 



Height of a rather large shell 20, greatest breadth 18, greatest diameter 13 mm. 



Remarks. — At first glance this species resembles Dr. Guppy's T. lecta from 

 the San Fernando beds, but the basal margin of that shell is somewhat sinuate 

 and pointed, while the Soldado species is truncate, and the hinge margin is also 

 straighter than in lecta, nor is there the flattening of the ventral valve noted by 

 Dr. Guppy in his species. 



This was one of the most abundant shells in the Soldado fauna. Trinidad 

 seems to have been the favorite haunt of the genus Terebratula during the 

 Tertiaries, for this is the fourth species described from that island. The genus 

 has lived on from the Devonian to the recent seas. 



This is the first species described from the Lignitic horizon. 



The writer takes pleasure in naming this shell in honor of Dr. Stanton, as a 

 slight appreciation of his kindness in identifying the Cretaceous fossils from 

 Hurupu, Venezuela. 



Locality. — Bed No. 8, Soldado Rock, near the Serpent's Mouth, in the Gulf of 

 Paria. 



Geological horizon. — Lignitic Eocene. Equivalent to the Lignitic of Alabama. 





Class VERMES. 

 Genus SERPULA. 

 Serpula clymenioides Guppy. Plate XIII, Figures 20-22. 



Spirorbis clymenioides Guppy, Quart. Jour. Geol. Soc, vol. XXII, p. 584, pi. XXVI, fig. 10, 1866. 

 Spirorbis clymenioides Guppy, Geological Magazine, new series, Decade II, vol. I, p. 444, 1874. 



Guppy' s original description. — "Tube coiled, discoidal, compressed; whorls 

 usually three to four, flattened or even fused together, with sinuo-radiate lines 

 of growth; periphery carinate; aperture constricted, circular; nucleus with an 

 obsolete aperture nearly as large as the terminal one. 



"The nearest species to this is S. spirulcea, Lam. (Spirulcea nummularis Schlot), 

 from which the present species may be distinguished in never having the last 

 whorl produced or separated. 



"San Fernando beds, Trinidad. Specimens frequently occur in the cherty 

 nodules, containing immense numbers of Orbitoides mantelli and Nummulina. y} 



Remarks. — This odd tube, simulating a helix-like molluscan shell, is made by 

 a worm of the suborder Tubicola (Sedentaria) of the genus Serpula Linnaeus. 

 This includes the majority of the fossil tubicolous Annelids. They build firm, 

 irregularly twisted, or sometimes spirally enrolled, free or adherent calcareous 

 tubes, frequently clustered in large numbers. The genus began in the Silurian, 

 and is rare throughout the Paleozoic; but becomes very common in the Lower 

 Cretaceous, and its recent distribution is world wide. S. spirulcea Lamarck, 

 the form most closely allied to that from Trinidad, is an abundant and character- 

 istic Eocene species of southern Europe. 



