648 SIB c. ELIOT ON NUDiBRANCHS [June 19, 



D. tuherculata" and under B. pardalis, the species described next, 

 " Tongue as in tlie last species, with the addition of a prehensile 

 collar." 



The animal obtained by the ' Siboga' should perhaps be known 

 as Disc, herghi. 



Platydoris papillata Eliot. 



%^=Ro'plodor%s desmoparypha B. var. 



(Eliot, Proc. Zool. Soc. 1903, ii. pp. 379-380. Bergh, in 

 Semper's Reisen, Suppl.-Heft i. p. 51 ; Siboga, p. 113.) 



In making an examination of further specimens of this animal, 

 I have found a spine in the accessory gland attached to the female 

 genitalia. The structure of the gland seems to be as described by 

 Bergh for Hoplodoris, but the spine is straighter. I cannot help 

 thinking that the species is Hoplodoris desmoparypha, or at least 

 very closely allied to it ; but I have not been able to find a labial 

 armature as described by Bergh. In one specimen there seemed 

 to be something like a plate or girdle on the labial cuticle, but it 

 was formed of fibres or filaments and not of the rods found in 

 DisGodoris and other genera. As a labial armature is generally 

 unmistakable and easily found, I do not think its presence can 

 have been overlooked. On the other hand, it is often developed 

 in very different degrees in different individuals of the same 

 species, and may perhaps disappear. In his first description 

 (S. R. 1. c. p. 53, note) Bergh seems to imply that it was vestigial 

 or imperfectly preserved. 



In my specimens the buccal cavity is black or brown. The 

 teeth are as previously described by me {I. c), but the outermost 

 are sometimes slightly and irregularly serrulate *. The formula 

 of the radula is about 40x80.0.80. There is a large sausage- 

 shaped prostate. 



The external characteristics correspond in most respects with 

 the descriptions of Hop. desmojxirypha, but the dorsal papillag are 

 far more developed and sometimes become branched processes 

 5 mm. long ; but there is much variety in this respect, as also in 

 colour. The spots and borders on the under side are particularly 

 variable. The gill-pocket is sometimes distinctly stellate, and 

 sometimes merely irregularly jagged or undulated. The tentacles 

 are in all specimens large but flat. The anterior margin of the 

 foot is deeply grooved and notched, and the upper lamina over- 

 hangs the lower. 



The animal has been observed to bury itself in sand, and the 

 dorsal papillae resemble bits of sand when it is alive. 



It may be doubted whether Hoplodoris is best regarded as a 

 separate genus or a section of Platydoris. Most of the characters 

 agree with that genus, and I do not think that the presence 

 of either an accessory gland and spine or of a labial armature 



* Pi-oc. Zool. Sec. 1903, ii. p. 379, fourth line from the bottom : " innermost " is 

 a misprint for " outermost." 



