On a new Tentaculate Cestode. 203 



In the male of ^1. merkliawis, Racovitza, from Tunbridge 

 Wells, both first maxilla) have five setas oil the apex of the 

 inner lobe, the first thoracic leg has the propod distinctly 

 oval, with the inferior margin straight and witliout any sign 

 of a triangular projection to meet the end of the tip of the 

 finger ; the fourth thoracic leg has on the carpus a distinct 

 row of about ten long spinules ; the first and second pleopods 

 are in close agreement with tlie characters assigned to tliis 

 species, the outer margin of the exopod of pleopod 1 being- 

 without any trace o£ an emargination. In the female from 

 Tunbridge Wells the inner lobe of maxilla 1 bears the five 

 plumose setaj both on the right and on the left sides; the 

 exopod of pleopod 2 is trapezoidal in shape as described by 

 Kacovitza. 



Racovitza has examined specimens of A. meridianus from 

 Dulwich and from Slapton Lea (Devonsiiire), and from 

 numerous localities in France. He finds it very constant in 

 its characters ; it ia, he says, not the only one of the series, 

 other allied forms being found in the Mediterranean basin 

 both in surface-streams and in underground waters. Of the 

 underground forms, two — A. cavaticus, Schiodte, and A./oreli, 

 Bl. — have already been described, and other forms will be 

 described by M. Racovitza in a forthcoming memoir. 



XSIX. — On a new Tentaculate Cestode. 

 By Frank E. Beddard, D.Sc, M.A., F.R.S., F.Z.S. 



The occurrence of tentacles (I do not include the " probos- 

 cides'^ of the Tetrarhyncha) is so rare among Cestodes that 

 a new example of this occurrence, characterising perhaps a 

 new species or genus, is worth bringing to the notice of 

 zoologists. So far we are only acquainted with one strictly 

 com|)arable instance, shown in the genus Schistometra, of 

 which 1 shall have something to say later. The only remain- 

 ing tentaculate worms of this group are the little-known 

 J'aratcenia and Fo/i/pocep/ialus, which are regarded by 

 Braun* as possibly identical, but of whose systematic 

 position the ascertained facts of structure do not permit 

 us to form a definite opinion; nor does the recent redcscrip- 

 tion of Paratdsnia by Southwellf definitely settle the matter. 



* In Bronn's * Klassen and Ordnungen des Thiereichs,' Bd. vi, 

 t ' Ceylou Mariue Biolojjical lieports,' pt. vi., Jau. 1912, No. 22. 



