Vol. 51.] MURCHISONIA AND ITS ALLIES. 217 



bounded by keels, and on the lower ones solid, flat, and bounded by 

 grooves ; it thus forms a connecting-link with the section Glyphodeta, 

 where, however, the whorls are more convex, and the band uniformly 

 solid and bounded by grooves. M. dalryensis differs in having the 

 band formed by three fine keels placed close together. In M. turri- 

 culata it is doubtful whether the sinual band is formed of a single 

 keel placed on the angle, or whether it lies below the angle and is 

 bounded by a keel on each side. It is convenient, however, to place 

 it in this section for the present. ' M. fusiformis is the species which 

 most resembles the type (if. turbinata, Schlot.), especially those forms 

 which have the keels bounding the sinual band undulating as shown 

 in pi. xxix. figs. 8, 9 of the ' Monograph of the Devonian Fauna, 

 etc' pt. iv. Pal. Soc. 1892 ; the plications here take the place of the 

 tubercles, while M. Verneuiliana comes very near the smooth 

 varieties, ibid. pi. xxx. figs. 5-10. 



In Hypertonia I would place conula var. convea'a, deplanata, 

 elongata, fastigiata, Kirlcbyi, M'Coyi, "plana, pentonensis, quadri- 

 carinata, and quinquecarinata var. pidchella. All these species have 

 the sinual band bounded by keels ; it is slightly grooved, and it is 

 also wide, except in M. elongata, M. pentonensis, and M. plana, where 

 it is narrow. M. conula var. convexa, M. deplanata, and M. plana 

 have the base flattened, while it is more or less produced in the other 

 species ; the mouth of the first is also more rounded than is usually 

 the case. Purther discoveries may lead to this section being sub- 

 divided. 



In Stegocoj:lia — compacta, variabilis, and Smitliiana. 



In Glyphodeta — splicerulata, zonata, ?tamiata, and fimbriearinata. 

 M. tamiata is doubtfully referred to Murchisonia, but has most in 

 common with the members of this section, the band which may 

 represent a sinus in the lip being flat and bounded by grooves. 

 M. fimbriearinata has slightly more angular whorls than the others, 

 and the band is ornamented by raised crescents. 



In Ccelocaulus — ? tuedia. 



In Cerithioides — telescopium and ? Oweni. 



In Caliendrum — vittata. 



In Worthenia — tabidata. 



The Carboniferous Murcliisonice are widely distributed, occurring 

 in Britain, Belgium, Germany, Russia, Spain, Carnia, India, 

 Australia, and North America. 



Foreign Species of Murchisonia. 



It is interesting to note the number of species found in other 

 countries, for the sake of comparison with the British species, and it 

 will be seen that the latter are the most numerous. 



De Koninck describes twenty-three species in the * Calc. Carb. 

 do la Bclgique,' M. acuminata, acuta, amarna, angulata, Archiaciana, 

 Brongaiartiana, conula, deornata, gracilis, Humboldtiana, ? maxima, 

 melanioides, nana, nodosa, obesa, pertusa, plicata, quadricarinata, 

 quinquecarinata, subomata, tenuis, turriculata, and Verneuiliana. 



