560 /. F, Walker — L, Greensand BracMopoda. 



the other shield-bearing Phyllopoda ; if a larval form, it may have 

 been the early stage of Prestwichia or some other of the Coal- 

 measures LimulidcB. Nor do we think it in the least probable that 

 the shield of Cyclus radialis was flexible or contractile, its original 

 segments being completely soldered together into one piece." 



Even amongst the Decapod Crustaceans we may, in the larval and 

 embryonal stages, find analogous forms to our fossil Cyclus. Thus Mr. 

 J. 0. Westwood in the Phil. Trans., Vol. I, Part II., 1835, figures from 

 Guilding's MSS., the larvaof a recent Land-crab having the appearance 

 presented in the subjoined Woodcut. 2 3 



The recent investigations of Dr. 

 A. S. Packard, jun., and the Eev. 

 S. Lock wood, tend further to con- 

 firm the opinion expressed by me in 



1868, that these forms may indeed pig^^es of Larva of a Recent Land-Crab. 

 be the larval stages of Prest- l- Nat. size. 2. Dorsal, 3. ventral aspect. 



wichia, Belinurus, etc., the ante-types in Carboniferous times of the 



modem King-crab. 



EXPLANATION OF PLATE XXIIL 



Fig. 1. Cyclus Rankini, H. "Woodward, from the Carboniferous Shale of 



Carluke, Lanarkshire, from the cabinet of Dr. Eankine, Carluke. 

 Enlarged 3 times. Dorsal aspect of carapace. 



Fig. 2, Cyclus radialis^ Phil., sp., from the Carboniferous Limestone, Vise, 



Belgium. This species also occurs at Bolland and Settle, in 

 Yorkshire ; Little Island, Cork, etc. (Original specimen in the 

 British Museum collection.) 



Fig. 2a. Side view of same. Both figures enlarged twice natural size. 



Fig. 3. and 3a. Cyclus bilobatus, H. Woodward, dorsal aspect and profile, from the 

 Carboniferous Limestone of Settle, Yorkshire. Enlarged ,4 times. 

 (From the Cabinet of Mr. J. H. Burrow, Settle.) 



Fig. 4. and ia. Cyclus forosus, H. Woodward, dorsal aspect and profile. Carbon- 

 iferous Limestone, Little Island, Cork, Ireland. Enlarged 4 times. 

 (From the Collection of Mr. Joseph Wright, Belfast.) 



Fig. 5. and 5a. Cyclus H'rightii, H. Woodward, dorsal aspect and profile. Carbon- 

 iferous Limestone, Little Island, Cork. Enlarged 4 times. (Col- 

 lection of Mr. Joseph Wright, Belfast.) 



Fig. 6. and 6a. Cyclus Harhnessi, H. Woodward, dorsal aspect and profile, from 

 the Carboniferous Limestone of Little Island, Cork, etc. Enlarged 

 4 times, (Collection of Mr. Joseph Wright, Belfast.) 



Fig. 7. and la. Cyclus [Salicyne) laxus, H. von Meyer, sp. Muschelkalk, Eottweil, 

 Germany. 



Fig. 8. and 8a. Cyclus {Halicyne) agnotus, H. von Meyer, sp. Muschelkalk, 

 Eottweil, Germany- 



Fig. 9. " Cyclus Brongniartianus," De Koninck. Hypostome of a Trilo- 



bite, probably of the genus Phillipsia, from the Carboniferous 

 Limestone, Bolland, and Settle, Yorkshire ; Blackrock, near Cork, 

 and Vise', Belgium. (From the Collection of Mr. Joseph Wright, 

 of Belfast.) Enlarged twice natural size. 



V. — On Secondary Species of Braohiopoda.^ 

 By J. F. Walker, M.A., F.G.S., etc. 



I HAVE already described in this Magazine several new species of 

 Brachiopoda from the Lower Greensand of Upwai-e^ ; since then 

 I have obtained many more specimens, and much kind assistance from 

 1 See Geol. Mag. 1868, vol. V., p. 399, PI. XVIII. and XIX. 



