80 Tramactions of tJw South African Philosophical Society. 



2. Id. Leachii, Aid. et Hanc. 



M. Atlantic, Mediterraneum. 



3. Id. Mediterranea, Jher. 



M. Mediterraneum. 



4. Id. tentacidata, Stimpson. 



M. Chincnsc. 



2. Idaliella, Bgh. 



R. Bergh, I.e., 1881, p. 145. 



NotiJBum medium lyeve. Discus labialis lamellis mandibularibus 

 instructus. 



1. Id. aspersa, A. et H. 



M. Atlantic. 



2. Id. pulchella, A. et H. 



M. Atlantic. 



3. Id. inaqualis, Forb. et Hanley. 



M. Atlant. 



4. Id. amoenula, B. 



M. capense. 



Idaliella am(enula, Bgh. n. sp. 



Color generalis aniraalis lacteus, notaeum (anterius) linea mediana 

 et laterali coccinea ornatum, rhinophoria flavescentia, cirrhi apice e 

 flavo rubri ; branchia et area branchialis coccineae ; latera corporis 

 superne linea coccinea ornata ; doi'sum caudte linea mediana coccinea. 



PI. XIII., figs. 6-11. 



Of tills beautiful form 5 specimens were sent, procured at rocks, 

 Gordon's Bay. 



Two individuals were dissected. The colour of the living animal 

 was " pink." 



The length of the animals was 8-13 mm. In the largest the 

 breadth of the back proper was 5, the height 4-5 mm. ; the height 

 of the rhinophores 2, of the cirrhi 3 mm., the diameter of the gill 4, 

 the foot 4 mm. broad, the tail 1 mm. long. — The ground colour was 

 milk-white, on the anterior part of the back a rather thin median 

 crimson line and another on each side of the back proper, somewhat 

 broader and more irregular, all three lines uniting in front; the 

 rhinophores yellowish; the upper third or sometimes half of the 

 cirrhi reddish yellow ; the area branchialis and the gill-leaves of 

 crimson colour; along the upper part of the sides of the body a 

 more or less interrupted line of similar colour, along the back of 

 the tail a median line of the same nature. 



