the ' Challenger^ Eryonidea. 225 



is a female 52 mm. long, carapace = 25 mm., breadth 19"5 and 

 distance from cervical sulcus to posterior edge of carapace 

 12 mm. The median spine-formula may be given thus: 

 2 1 1 1 1 1 1 : C . . , , 



the spines in the posterior part being mere tubercles. The 

 lateral edge is armed with 9 + 4 + 14: spines. The branchial 

 ridge carries 30-32 small spines. There are no spines on the 

 gastral area and none on the cervical ridges. The figure 

 given by Bate is not particularly good. 



Pentacheles Icevi's, Bate. 

 Polycheles lavis, de Man, /, c. 



Two specimens are referred to this species. There is not 

 much evidence apart from the labels that they are the objects 

 referred to in Bate's text and figures. 



Station 214 300 



Locality 4° 33' N., 127'" 6 E. 33° 42' S., 78' 18' W. 



Specimen No. 1 (type). No. 2 (cotype). 



Length of carapace .... 18 mm. 20 mm. 



Total length 37 42 



Do. in per cent, of cara- 

 pace 205 210 



Breadth in do 74 70 



J)istanee from cervical 

 to posterior edge of 



carapace in do 46 46 



Median ridge-formula of no. 1 : 



2: :: : : : 1 : : : : 2 : : : : : 1 : : : : C: : : : : : 2: : :: : : : : ::, 

 <lo. of no. 2 : 



2::::::::::::2:::;1:::::: C:::::::l : : : : 2 : : 2 : . : : : : : :. 



Lateral edge-spines : 



No- 1 : 8+3+14, no. 2": 8+3+9 



Bate gives the total length as ''33 mm. (1*5 in.)" and 

 *' 4:7 mm. (1'75 in.) " respectively, and states that the dorsal 

 surface is unarmed save for the two rostral teeth and the two 

 single spines between these and the cervical sulcus. As will 

 be seen from the above formulas, the median ridge is in both 

 specimens armed in a way similar to P. debilis, Smith, and 

 P. arynatus, Bouvier, and between the more prominent spines 

 the ridge is all along armed with a double row of small 

 tubercles (designated by a series of :::::: in the formuhe 

 above). 



Ann. cfc Mag. N. Hist. Ser. 9. Vol. vi. 15 



