PLATE IV. 



Figs. 1-6. Aidhrapaldmion russeUianits (Snlter) . . . . . . . . . . . . Page 30. 



1. Mag. 3 fliam. Carapace seen from above. Locality, Greentjairs, 34 niile.s N.N.E. of 



Airdrie, Lanarkshire. T. 2763'^. 



2. Mag. 3 diam. Underside of trunk .showing wide .sternites, with row of phites {phi.) .-md 



gilLs ((/) on left side (right hand of observer), beyond which are seen fragments of both 

 branches of seven limbs : an. antenna, e. eye, ^n.p. niandibul.ar palp, ni. body of mandible, 

 m^. molar edge of mandible, via. maxilte, max.p. palp of ma.xillipede, m.g. ? p.ipillae 

 upon which the male genital organs open, d. donl)lure of cai'apace. Same locality. 

 T. 2766". 



3 Presented to Survey Collection by R. Dunlop. Mag. 2 diam. Trunk and part of tail seen 

 fi'om above. The specimen is partly pre.served in iron pyrites, and the carapace has 

 broken away with the counterpart revealing the ventrally-placed organs, which are 

 domewhat displaced : e. eyes, a. antennules, an. antenna;, s. basal scale, m. mandible, 

 m.]). mandibular palp, c. carapace, en. endopodites of ti'unk limbs, ex. exopodites of same, 

 ;/. gills. The backs of the anterioidy [ilaced tail segments ai'e seen, and where thev are 

 broken away the wide sternites of one segment with the articulations for tlie pleopods 

 can be seen. The tail is folded up, and this reveals the natural arching of the body 

 where the segments lie at i-iglit angles to the bedding planes of the shaly ironstone. 

 Same locality. 



4. A little over nat. size. Cai-apace foLled together. Shows the serrated side-keels, the 



doublure {d.), and the short conical forwnrdlv-directed spines on sides of carapace. 

 Same locality. T. 2753''. 



5. Presented to Survey Collection by Pi. Dunlop. .Mag. 3 diam. Part of tail and tail fan : 



t.l. terminal lobe, a.s. acces.sory swimmerets. Same locality. 



6. Dunlop Coll. Nat. size. Sketch of specimen belonging to Mr. R. Dunlop, .showing the 



trunk and tail. The i)osition of the sense organs of head is well seen. The tail is 

 .slightly displaced or driven in, but the tail fan is well shown. Same locality. 



Fig. 7. Anthrapali'inon russeUiauus, var. spinidosiis var. nov. Mag. Ij diam. Carapace seen from 

 above. Same locality. T. 2768" ' Page 36. 



Figs. 8-10. Pi/yocepludiis cooperi Hu-xley . . . . . . . . Pages 33, 37. 



8. Mag. 1| iliam. Reproduction of Huxley's original figure from (Juart. Journ. Geol. aSoc, 

 1857, vol. xiii., pi. xiii., fig. lb, p. 367, for comparison with figs. 2 and 3 (above), and 

 with plates i., ii., and iii. 



S. Mag. li diam. Reproduction of Huxley's figure, loc. cit.. fig. 3, for comparison.* 



10. Nat. size. Reproduction of figure by H. Woodward of Scottish specimen from Kilmaur.s, 

 Ayrshire, taken from Trans. Geol. Soc. Glasgow, 1867, p. 234, pi. iii., fig. 2, for com- 

 parison. 



* Figs. 8 and 9 are drawn of the same size as Huxley's original figures, and are tlierefore magnified lA diameters, 

 not '2 diameters as shown in present plate. 



