APPENDIX. 



Page 121. 



I stated that the genus Calceola was confined to the Devonian epoch, and that I was acquainted 

 with buc one well-authenticated species. Dr. Fr. Roemer has, however, recently informed me that he has 

 found a second species in true Silurian rocks, near Brownspost, in the State of Tennessee, N.A. 1 



Pages 122, 124, and 125. 

 For " Spondylobus" read " Spondylolobus" (M'Coy). 



Page 133. 

 Family — LinguliDjE. 



Page 134. 



Line 3, for "beak of the valve," read "beak of the ventral valve." 



„ 10, for "left by the pedicle muscle (a)," read "left by the post-adductor muscle." 



,, 13, for " caused by the posterior," read "caused by the anterior." 



„ 16, after "last-described impressions," add "in the dorsal valve." 



„ 17, for "combined extremities of the anterior pair," read "extremities of the anterior pair of 

 retractor muscles." 



The animal of Lingula anatina having been minutely examined by Mr. S. P. Woodward subsequently 

 to the publication of my 'Introduction,' I am now enabled, with his kind permission, to reproduce the 

 woodcuts and description recently published by that able naturabst, in the second portion of his excellent 

 and valuable ' Manual of the Mollusca.' 



1 Note on Calceola Tennesseensis, n. sp., a true Silurian species of the genus (extracted from the 

 unpublished manuscript of the 'Lethseca Geognostica, 1st Period,' by Fred. Roemer. 



Calceola Tennesseensis, Fred. Roemer, n. sp. 



Calceola sandalina, Froost. 'Fifth Report on the Geology of the State of Tennessee,' Nashville (p. 47, 

 1840). This species, although similar to Calceola sandalina, differs from the type of the genus by the 

 following characters : 



1. The shell is much thicker than in C. sandalina, and the space for the reception of the soft parts of 

 the animal in consequence reduced to a shallow hole. 



2. The edges separating the area of the larger valve from the convex posterior part of the valve are 

 much less angular, or more rounded. 



3. The area of the smaller valve, which in C. sandalina falls into the same plane, or nearly so, is 

 inclined backwards, and forms an obtuse angle with that of the larger valve. 



Locality. Not very rare in calcareous strata of the age of the Wenlock Limestone of England, asso- 

 ciated with Orthis elegantula, Caryocrinus ornatus, Pentatremites Reinwardtii, &c. 



Calceola pyramidalis, Girard (Leonh. and Bronn's ' Jahrb.,' 1842, p. 232, f. a, b, c), from the Silurian 

 strata of Gothland, is not a Mollusc, but a Zoophyte, and synonymous with Goniopkyllum pyramidale, 

 Edwards and Ilaime, 'Archive du Mus.,' vol. v, p. 404 (Fr. Roemer). 



