THE SHRIMP BATHYPALAEMONELLA PANDALOIDES — HOLTHUIS 521 



Remarks.— The present form is the second species loiowTi of the 

 genus Bathyj>alaemonella Balss, It is closely related to B. zimmeri 

 Balss but differs from that species in the following respects: 



1. The rostrum bears many more teeth. In B. zimmeri the rostral 

 formula is ^^^- This formula in B. pandaloides is ^h^t+i Though 

 Balss in his description states that only three teeth of the dorsal mar- 

 gin of the rostrum are placed behind the orbit, his figure shows five 

 there. 



2. The scaphocerite in B. zimmeri has the anterior imier angle more 

 produced than in B. pandaloides. 



3. The last joint of the second maxiUiped is slenderer in Kathbun's 

 than in Balss's species. 



4. The dactylus of the last three pereiopods are quite differently 

 built in the two species. In B. zimmeri the dactylus is stated to be 

 provided with four or five small denticles at the posterior margin, 

 while in B. pandaloides only two denticles are present, which are very 

 curiously placed at the same level, one at each side of the posterior 

 margin of the dactylus. 



Unfortunately, both specimens of B. pandaloides lack the larger 

 second leg, so that nothing can be said about possible differences in 

 the shape of that appendage in the two species. 



Bathypalaemonella zimmeri Balss is known only from the original 

 record, off the east coast of Somaliland, latitude 6° 18' N., longitude 

 49° 32' E., from a depth of 1,079 meters. 



In 1925 Balss correctly placed the genus in the family Campylono- 

 tidae, after having put it in the family Palaemonidae in 1914. There 

 is no doubt that Bathypalaemonella is a campylonotid, but I do not 

 agree with Balss (1925, 1927) and Sollaud (1910, 1913) that this family 

 belongs to the superfamily Oplophoroida Borradaile. Sollaud (1910, 

 1913) mentions the following points in favor of placing Campylonotus 

 in the Oplophoroida: 



1. The number of spinules on the dorsal surface of the telson is 

 8 or 10; in the Palaemonidae this number always should be 4. 



2. The upper antennular flagellum is not bifurcated as it is in the 

 Palaemonidae. 



3. The mandible is not cleft. 



4. The maxillulae have two laciniae, which both are cleft. 



5. The palp of the first maxilliped is bi- or tri-articulated. 



6. The exopod of the third maxilliped is jointed. 



7. The second maxilliped consists of five joints. 



8. Arthrobranchs are present on the first four pereiopods. 



9. Epipods are present at the base of the first four pereiopods. 



That the character of the number of dorsal spinules is of no im- 

 portance is shown by the fact that in some Pontoniinae there are eight 

 dorsal spinules on the telson (Periclimenes alcocki Kemp) , while in an 



