part 2] A( /./■'<L\A AND ACIJsrUDKS, 1\) 



t'onn. At tliat tiinr 1 did not know ot" the fxistonec of any of the 

 ty)n.'s of De KoniiK-k's oarlitT work (* Descr. Aiiiiu. Foss. Timt. Carl). 

 Helg.' lSJr3), and founded niv remarks on tlie type seleeted when 

 lie wrote his later work ('Fa line Cale. Carh. BelV-" 1881 k lS83j, 

 which is in the Musee Hoyal d'Histoire Naturelle at Brussels, as 

 well as on similar specimens from the same locality in that and 

 other collections. 1 understood him to tell me that all his early 

 ty])es had gone to America ; subsecjuently, however. 1 had occasion 

 to visit the Kcole des Mines, Paris, where throui^h the ccnn-tesy «)f 

 M. Douville 1 was shown some tv))es which had heen j)resented by 

 l)e Ivoninck in ISKi.^ Amon*:^ them were JJ/n-cJu'sofUff siriaf uhi 

 (in. VI, rtirs. lU cV: 11 I and .1^. sHhsiilcnfn (PI. VI, ti*,'. Ki). At 

 first sight they a])peared to he distinct sj^ecies as described, but a 

 close study of them, as well as of a large series of both Belgian 

 and Britisli specimens, has convinced me that they are eonspecitic. 

 Since De Koninck does not refer to J/, sithtitt/cdtd in his later 

 work, he may have realized this, though he has not published it. 

 In the Liege Museum 1 saw three individuals from Vise un- 

 doubtedly' eonspecitic, two of which were marked A. sfriatula and 

 the other M. sf/fjs///<-iiht. The ty])e specimens are more or less 

 distorted by pressure. That of M. sHhafilcdtd is rather Hattened. 

 so that, from one i)oint of view the s])iral angle apj)ears greater 

 than it nnist originally have been, and this defect is exaggerated 

 in De Koninck's tij^ures ; the surface is also somewhat worn, there- 

 fore he describes it as having bands instead of threads and grooves. 

 The two exam])les of M. sfrinft/Zn Are compressetl in such a manner 

 as to make tlie whorls a))])ear more angular; in one, consisting of 

 the body and ])enultimate whorl, this is only slightly so, but in the 

 other the distortion is greater, so that the sutures are rendered 

 very oblique and the whorls still more angular : the ornamenting 

 threads on both are well preserved. The specimen marked as the 

 type (»f At'llnliKi iitriatnio in the Brussels Museum is almost 

 normal; but it is smaller, and the surface is much worn. 



This s))ecies exhibits a certain amount of variation, both in form 

 and in th<' number and strength of the ornamenting threads. In 

 some sliells the whorls are more exsert. as in two |)urchased from 

 De Koninck by the British Musemn (Natural History) (i liM)Sl, 

 wliieh are marked M. sfridt iil(( in his own handwriting, in the 

 s|K'cimen described as Rhnhdoaiti ra srI ki rk'i i, and also in a small 

 example from Hainnyres. Lanarkshire (PI. VI, Wii:,. lo). In the 

 gieat«'r number of sjieeimens, however, the earlier whorls are closely 

 <(>iled and increas*' slowly, in such wise that tliey are lower and 

 broader than the later whorls: thus these slu'lls are somewhat c(tnvex 

 in contour, and when immature have a greater spinil angle than 

 the anterior )M)rtion viewed alone ha.s. The holotype of M. sith- 

 sitlrnfd antl many specimens from Settle have this compact foi*ni, 

 ( PI. VI. tiir. i:i. \ op. cii. pi. V. liu's. (1 7i. whih- the two tyju's of 



' Animaire (f«'ol, Uiiivors. 18S.'). • M»i«..'m'h tS: Collections F'ftrtieidi.Te-, Puri;*, 

 Kfole <los Mines. C.»ll. .le Piil.'ont." p. 211. . 



