470 MISS E. M. R. WOOD ON THE LOWER LUDLOW [May IpOO, 



MONOGRAPTUS R(EMEBI (BaiT.). (PI. XXV, figS. 13 A & 13 B.) 



1850. Grraptolithus Rcemeri, Barrande, ' Grapt. de Boheme' p. 41 & pi. ii, figs. 9-11. 



Polypary. — 3*8 to 7'3 cm. (1*5 to 2 - 5 inches) long, with a 

 characteristic form, the dorsal margin being slightly convex at the 

 proximal extremity, then concave for the greater part of its length, 

 and again convex at the distal end. The width at the first theca is 

 •89 mm. ('035 inch), increasing for the first four thecse at the rate 

 of *19 mm. (-0075 inch). After that increase it is more gradual, the 

 maximum width, 2'9 mm. ('115 inch), being attained at about the 

 fourteenth theca. Some examples, however, measure as much 

 as 3*6 to 4-2 mm. (*14 to *17 inch). Frequently the polypary 

 appears to narrow towards the distal end. Distal prolongation of 

 virgula short, and rarely seen in British specimens, but it may be as 

 long as 2 cm. in Bohemian forms. 



Proximal Extremity. — Sicula about 1-8 mm. (*07 inch) long, 

 and *32 mm. (-012 inch) wide, hence more than 5 times as long 



as wide, and extending to about the 

 Fig. 17. — M. Rcemeri apertures of the second theca. Aperture 



x 5. provided with a long ventral spine. 



First theca the same as in M. colonus. 



T h e c ae. — Thirty-four to twenty- 

 eight in the inch (thirteen and a half 

 to eleven in 1 cm.), inclined to the 

 axis at an angle of 40° to 45°. Thecae 

 long, narrow tubes, the adult thecae 

 being 5 or 5| times as long as wide, 

 and overlapping for two-thirds of their 

 [Proximal extremity, showing length# Aperture wide and concave 

 the sicula: enlargement ol • i i • t d\ j j. 



the reverse side of fig. 13 a (somewhat convex in relief) and at 

 in PI. XXV. J right angles to the direction of the 



theca. Proximal three or four thecae 

 only about 3 times as long as wide, inclined to the axis at a 

 high angle, overlapping for half their length, and with the 

 aperture recurved. 



M. Rcemeri is a well-marked species characterized by (1) its 

 peculiar double curvature, (2) its rapid increase in width, and (3) the 

 amount of thecal overlap. This species has not been correctly 

 identified in England hitherto, owing probably to its rarity. It 

 does not seem to have been yet recognized in Sweden, unless 

 Tuilberg's M. colonus 1 is referable to it, but Dr. Barrois records it 

 from France, and an isolated specimen was figured by Heidenhain 

 from the Graptolithengestein. Nowhere, however, does it occur so 

 abundantly and characteristically as in Bohemia. This species is 

 quite distinct from M. colonus, though Prof. Freeh seems to regard 

 its separation from M. colonus as ' at least doubtful.' 



Foreign Localities. — Bohemia (Butowitz, Borek, Slavik, etc.), 

 Graptolithengestein; France (Languedoc, Britanny, etc.) ; Scania? 

 (Knashufvud). 



1 ' Skanes Graptoliter ' pt. ii (1883) Syer. Geol. Undersokn. ser. C, no. 55, 

 pi. i, fig. 21. 



