222 Mr. 0. Suiid on 



The following- additional particulars are of interest in 

 describing the specimens : — 



Specimen no. 1. — This is the type o£ the species, and is 

 figured in pi. xviii. and pi. xix. G" , but rather inaccuiately 

 as far as the spines are concerned at least. Tiie armature of 

 the median ridge may be expressed by the following formula, 

 employing the same symbols as above, under Eri/oueicus 

 ccecus :— 



1 1 1 112 1 1 C 2 1111. 



The lateral edge carries 29 spines, of which 7 are situated 

 forward of, 4 between, and 18 behind the branches of the 

 cervical sulcus (7 + 4 + 18). The surface of the carapace is 

 covered by a dense " fur " of short spinules except on the 

 elevated ridges, which are stnooth. The hook in the. middle 

 line on the back of the first pleosomite is quite rudimentary. 



Specimen no. 2. — Median ridge spine-formula: 

 1 1 I 1 1 I 2 r C V 111. 



Lateral edge spine-formula : 



Right side 11+6+21, left 10+G+-U). 



Tins spjecimen furthermore differs from no. 1 in the following 

 particulars: — 



(a) Two of the median spines (marked ' in the above 

 foruiula) are elastic and bend when pressed, in these respects 

 resembling the blunt-tipped spines found in the correspoudiug 

 place in all Eryoneicus. 



(J)) The frontal ei^ge has nearly no orbital sinus, a feature 

 which is well-marked in the type-s[)ec:men. 



(c) The third joint cff the anteiinular peduncles is only 

 half as long as tiie second, in no. 1 the three joints are of 

 about the same length. 



(d) The last joint of the antennal peduncle is about 50 °/q 

 longer than the penultimate, in no. 1 it is of equal length. 



Specimen no. ;?. — Median line spine-formula : 



1 1 1 1 1 C (posterior part smooth). 



Lateral edge spine-formula : 



5+3+8. 



Posterior portion of the edge smooth. " Fur " on carapace as 

 in no. 1. 



