1922.] S.Kemp: Notes on Crustacea Decapoda. i^y 



Periclimcnes (Periclimenes) scriptus (Risso). 



K)i6. Urocaris de Mani, Balss, in Micliaclsen's Beiir. Kennt. Meeres- 



fartn- West-afrihas II, p. 29, text-fig. to. 

 1917. Periclimenes (Cristiger) scriptu s, Borradaile, Trans. Linn. Soc. 

 (2) Zool. XVII, p. 362 (synon.). 



I am unable to find in Balss' description any character which 

 will distinguish his TJrocaris de Mani from P. scriptus, the type of 

 the genus Periclimenes. 



■ P. scriptus is common in the Mediterranean and has been found 

 at the Channel Is. ; if I am right regarding the identity of the 

 specimen described by Balss its distribution extends southwards 

 along the West African coast to French Congo. 



Periclimenes (Periclimenes) amethysteus (Risso). 



1826. Alplietts amethystea, Risso, Hist. nat. Europe Merid. V, p. 77, 



pi. iv, fig. 16. 

 1863. Anchistia amethystea, Heller, Crust, zudlich. Europa, p. 258. 

 1917. Periclimenes (Falciger) amethysteus, Borradaile, Trans. Linn. 

 Soc. (2) Zool. XVII, p. 370. 



Other references are given by Borradaile. The original des- 

 cription is based entirely on colour and I know of no other cha- 

 racter bj' which the species can be separated from P. scriptus. 

 Heller's account of the colouration differs considerably from that 

 given by Risso and the only definite points of distinction appear to 

 be those which I have noted above in the key to the species of the 

 subgenus. At the Oceanographical Museum at Monaco I have 

 examined specimens from Bone, in Algeria, which bore the name 

 amethysteus, but was unabje to find any difference in structure from 

 P. scriptus. The validity of the species must remain uncertain 

 until fresh information based on living material is forthcoming. 



P. amethysteus is known only from the Mediterranean. 



Periclimenes (Periclimenes) impar, sp. nov. 

 (Plate III, fig. I.) 



This species is allied to the four preceding forms but differs in 

 the much broader dactylus of the last three pairs of legs. 



The rostrum is a little longer than the antennular peduncle, 

 but does not reach the end of the antennal scale. The upper margin 

 is convex and in the single specimen examined bears 9 more or less 

 evenly spaced teeth. The hindmost tooth is placed on the carapace 

 behind the orbit but is not separated from the second by a greater 

 distance than that between the second and third. The middle 

 teeth of the dorsal series are the largest. On the lower border 

 there are 2 teeth, placed near the tip, and the margin from the pos- 

 terior tooth to the base is nearly straight. 



There is no supra-orbital spine. The antennal spine is sharp 

 with the hepatic behind it but on a lower level. The eyes are 

 rather stout and the ocular spot touches the cornea. 



