OBOLID^. 519 



The largest ventral valve received from Matthew has a length of 9 mm. ; width, 6 mm. The 

 area of the ventral valve is long and divided midway by a narrow, tapering pedicle groove, and 

 toward the lateral margin by a well-marked flexure line. The area of the dorsal valve is unusu- 

 ally long and well marked; the flexure lines are strong and outlme a broad, shallow groove 

 between them (PI. XXXVIII, fig. le). 



A cast of the ventral valve shows a slight trace of the visceral cavity, also the anterior 

 lateral muscle scars. A few outlines of the vascular markings are preserved in casts of the 

 dorsal valve, also the transmedian and outside or middle lateral muscle scars which occur just 

 within a narrow ridge that borders the somewhat flattened margin of the interior of the valve. 



Observations. — The original figure of this species [Matthew, 1890, PI. VIII, fig. 4] is quite 

 unlike those subsequently given by Matthew [1895a, PI. II]. The first type must have been 

 distorted, or else it is a different species. 



With original specimens to compare and study I consider the specimens referred to Lin- 

 gulella cf. granvillensis by Matthew [1895a, p. 114] to be identical with L. martinensis. The size 

 and form of the valves, convexity, and surface markings all serve to strengthen this conclusion. 

 The ventral valve, figured by Matthew [1895a, PI. II, fig. 7a], is an impression in the shale, the 

 cardinal slopes of which have been broken away. The dorsal valve [Matthew, 1895a, PI. II, 

 fig. 7b] may be compared with the dorsal valve of L. martinensis [1895a, PL II, fig. 6d]. 



Matthew [1895a, p. 114] described the occurrence of the central and lateral scars in the 

 ventral valve, but he does not show them in his figures, and I can not clearly see them in the 

 type specimens received from him. 



The specific name is derived from St. Martins, in which the type specimens were collected. 



Formation and localitt. — Middle Cambrian: (2g and 2f)'' Sandstones of Division Ihl; (21i) sandstones of Divi- 

 sion lb2; and (2i) sandstones of Division lb3; all in Matthew's [1895, p. 108] Protolenxis zone on Hanford Brook, 

 St. John County, New Brunswick. 



LlNGULELLA MINOR (Matthcw). 



'^' Plate XXXVII, figures 3, 3a-g. 



Idngulella starri minor Matthew, 1892, Trans. Roy. Soc. Canada for 1891, vol. 9, sec. 4, No. 5, pp. 58-59, PI. XIx, 

 figs. 5a-b. (Described and discussed as below. It is a new variety, though not so described. The specimens 

 represented by figs. 5a and 5b are redrawn in this monograph, PI. XXXVII, figs. 3 and 3a, respectively.) 



The original description by Matthew follows : 



This neat little species is referred to Lingu lella starri on account of the sculpture, though it is different both in form 

 and size. It is only about two-thirds of the size of that species, and is more prolonged in front. The dorsal valve also 

 is ovate, not oblately orbicular as in the type. 



The sculpture consists of concentric ridges, which appear crenulated owing to the interrupted, faint, radiating 

 ridges that traverse them. At intervals there are stronger concentric lines marking stages of growth. The ridges are 

 not so sharply marked as in L. starri, and the shell is much thinner. 



Length of ventral valve, 11 mm. ; width, 9 mm. The dorsal valve is 1 mm. shorter. 



Observations. — The types of Lingulella starri are in this naonograph referred to Lingulella 

 (Lingulepis), and the variety minor of Matthew [1892, p. 58] to Lingulella as a distinct species. 

 During the summer of 1899 I visited the type locaHty on Long Island, and found this shell 

 in the shales, and also a smaller shell that appears to be the young of Lingulella minor, in a fiiie, 

 compact, shaly sandstone, and in lenticular masses of limestone interbedded in the shales. 

 There is also great variation in outhne and size of the shells in the siHceous shale. 



Formation and locality. — TTpper Cambrian: (2x) b Thin-bedded sandstones of Division 2 of Matthew, on the south 

 shore of Long Island, Kennebecasis Bay [G. F. Matthew, lS98b, p. 38], St. John County, New Brunswick. 



(3n) Thin-bedded sandstones on Salmon River, Gillis Hill, 13 miles (20.9 km.) south of Marion Bridge, eastern 

 Cape Breton, Nova Scotia, Canada. 



a 2f is the type locality, thougli tlie specLmeTis in the United States National Museum collections to which that number is assigned were 

 collected later than the type specimens. 



b2x is the type locality, though the specimens in the United States National Museum collections to which that number is assigned were 

 collected later than the type specimens. 



