OBOLIDiE. 



567 



Neoholus wynnei Waagen, 1891; Mem. Geol. Survey India, Paleontologia Indica, ISth. ser., Salt Range Fossils, 



vol. 4, pt. 2, PL II, figs. 10 and 11. (No text reference. Figs. 10 and 11 are copied from Waagen, 1885, PL 



LXXXV, figs. 2 and 1, respectively.) 

 Lakhmina Knguloides (Waagen), Hall and Clarke, 1892, Eleventh Ann. Rept. State Geologist New York for 1891, 



p. 234, figs. 243 and 244. (No text reference. Figs. 243 and 244 are copied from Waagen, 1885, PL LXXXV, 



figs. 5 and 6, respectively.) 

 Neoholus warthi Waagen, Hall and Clarke, 1892, idem, p. 245, figs. 250 and 251. (No text reference. Figs. 250 



and 251 are copied from Waagen, 1885, PL LXXXIV, figs. 6 and 7, respectively.) 

 Lahhmina Knguloides (Waagen), Hall and Clarke, 1892, Forty-fifth Ann. Rept. New York State Museum for 1891, 



p. 550, figs. 243 and 244. (No text reference. Figs. 243 and 244 are copied from Hall and Clarke, 1892a, figs. 



243 and 244, p. 234.) 

 Neoholus -warthi Waagen, Hall and Clarke, 1892, idem, p. 561, figs. 250 and 251. (No text reference. Figs. 250 



and 251 are copied from Hall and Clarke, 1892a, figs. 250 and 251, p. 245.) 

 Lakhmina linguloides (Waagen), Hall and Clarke, 1892, Nat. Hist. New York, Paleontology, vol. 8, pt. 1, p. 28, figs. 



13 and 14. (No text reference. Figs. 13 and 14 are copied from Waagen, 1885, PL LXXXV, figs. 5 and 6, 



respectively.) 

 Neoholus warthi Waagen, Hall and Clarke, 1892, idem, p. 84, figs. 39 and 40. (No text reference. Figs. 39 and 



40 are copied from Waagen, 1885, PL LXXXIV, figs. 6 and 7, respectively.) 

 Lakhmina linguloides (Waagen), Frech, 1897, additional plates inserted in 1897, in Lethsea geognostica, pt. 1, Lethaea 



palseozoica, atlas, 1876, PL I a, figs. 4a-b. (Figs. 4a and 4b are copied from Waagen, 1885, PL LXXXV, figs. 



5 and 6, respectively.) _ 

 Neoholus warthi Waagen, Frech, 1897, idem, PL I a, figs. 5a-b. (Figs. 5a and 5b are copied from Waagen, 1885, 



PL LXXXIV, figs. 7 and 4, respectively.) 



The generic description embraces the characters of the species. By the courtesy of Dr. 

 T. H. Holland, director Geological Survey of India, I have had the opportunity of studying 

 the type material and thus of coming to an in- 

 dependent opinion as to the genus and species. 



Waagen [1885, p. 758] states that the sur- 

 face of the shell is perfectly smooth. I find 

 that some of the specimens are worn nearly 

 smooth, while others preserve concentric lines 

 and striae of growth. The shells show the same 

 variation of surface as do shells of Oholus that 

 have lived on a sandy bottom and been more or 

 less worn by the attrition of the sand. 



The second species of the genus, "Neoholus 

 wynnei," differs from the types of Neoholus 

 warthi, according to Waagen [1885, p. 760], only 

 in having the surface strise more distinctly pre- 

 served. This character does not appear to be 

 of specific value, as there is considerable vari- 

 ation in this respect among the type specimens 

 of Neoholus warthi. 



The relations of Neoholus warthi and LaJchmina linguloides have been mentioned under 

 observations on the genus Neoholus (page 565). 



The shell described as " Davids onella squama" by Waagen [1885, p. 766] appears to be 

 a dorsal valve of "Lakhmina linguloides." He figures it [1891, PI. II, figs. 6a-b] as Neoholus 

 warthi. I found some rock attached to the cardinal margin in such a manner as to give the 

 effect of a low pointed apex. On clearing the rock away the apex was found to be marginal 

 and the cardinal border the same as in the dorsal valves of " Lalchminxi linguloides." The 

 shell is the largest found at Jutana. It has a length of 13 mm.; width, 14.5 mm. 



The specific name was given in honor of Dr. H. Warth. 



Formation and locality. — Middle Cambrian: Lower portion of the "Neoholus beds" of the Khussak group, 

 in purplish-colored, fine-grained, micaceous sandstones at the following localities [Waagen, 1885, p. 759]; (357c) 

 near the fresh-water springs in a gorge above the salt mines at Kiura (Klhewra); (357a) at Jutdna; and (357b) at Ch61 

 Hill; all in the Salt Range, India. 



A B 



Figure il.— Neoholus warthi Waagen. A, Interior of dorsal valve 



showing area, median ridge, and thiclcening of the shell beneath 



the visceral area. On the right side the main vascular sinus is 



clearly shown. This drawing is from a cast of a dorsal valve in 



which the platform has not been developed. B, Outline of a 



platform, median ridge, and vascular sinuses in a dorsal valve, 



obtained by removing the outer shell by acid (X 3). (See p. 565.) 



The specimens represented by figures 47A and 47B were collected 



in the Khussak group of the Middle Cambrian at Kiura (KhewTa), 



Salt Range, India. The specimen represented by figure 47 A is shown 



in Plate I, fig. 4b, also, the present figure being the correct and later 



drawing from a cast made in a natural mold. The specimen from 



which the cast was taken is in the collection of the Geological Survey 



of India (Cat. No. 3/780). 



