844 



ME. F. P. bepfoud as holothueians [Nov. 15, 



symmetry, except the mid-ventral radial pair, the left of which is 

 smaller than the right : no mention is made of the tentacles 

 forming more than one circle, but as they were in a retracted 

 condition this may have been overlooked. 



Ps. acicula Semper (Liidwig, 1875, ?. c. fig. 17 b) also possesses 

 20 tentacles, of which 15 (10 large and 5 small) form an outer 

 circle surrounding 5 smaller tentacles corresponding to the radii 

 (v. Diagram I.) (from Bronn, Z. c. p. 95). 



Fs. intercedeiu Lampert. — Lampert (J. c.) describes 18 tentacles, 

 of which 5 form an inner circle, the inner tentacles being as large 



N3OO0/ bOOcf >-iOOrf 

 O ( 1 ) 00 ( n« 5 Or) ( "• ) O 



fix " ■ ^ ,0° ■ ' -US'" """""V?°a 



OQ.pO" 

 \oOOo' 



0° °o 



O C'l") O 

 % ' rf 



O 



00 ^->^ 



oO 



Q 



'o\d 



O 



o 



\OOd 



o 



IIIB i 



-....y o 



o 



p- 



^o,od 



o 



V 



NoOOo- 



° o 



0° 



o 



0° 



JIIc 



o 



'a 



vOO^^ 



o 



0° 



o 



"°0 



IIIdI 



060 



o 



^, 



OOpQO 



0° . °o 



00 



lilt 



.0' 



,0 



o 



OoopqO 



Diagram of oral tentacles of Pseudocucumis. 



The tentacles are supposed to be viewed from in front, the month being 

 represented in tlie centre. The relative sizes of the circles correspond apjji-oxi- 

 niately to the relative length and breadth of the tentacles, the relative distances 

 being also approximately correct. The arrows indicate the position of the 5 

 radii. 



Fig. I. Pseudocucumis a«'cM/a (Semper), after Ludwig in Bronn's 'Klassen,' 



/. c. p. 96. 

 Fig. II. Ps. japo-iiica (BAX). a, b. From two specimens in the British Museum. 

 Fig. III. Ps. africana (Semper), s. After Lud wig in Bronn's ' Klussen.' /. c. p. 9t5 ; 



B, c, D, E. From specimens in the present collection. 



