51 



The; oenus Argivora was basetl b\- Lesueur oii a small mollusc, first described by hini ') 

 as a naked Cvmbulia ; hc called it Cyinöulia parva, but proposed to erect for this torm the 

 new genus Argivora. The species has never been figured, and its description is very incomplete. 

 Perhaps it is a small specimen of Cymbuliopsis, but absolute certainty cannot bc obtained. 



Corolla was established by Dall ") on a small specimen (Corolla spectabilis)\ the genus, 

 though very nearly related to Ticdeiiiannia, differed from it in the pendant body and absence 

 of a shell. The genus Corolla was declared by Pelseneer ') to be synonymous with Gleba. 

 But Dall ^) himself afterwards adknowledged the identity of Corolla with Cymbtiliopsis. 



Cvmbulia of Péron et Lesueur ^) includes the species on which the whole family has 

 been based. Cynibiilia peroni from the Mediterranean is very well known and distinguished 

 from other forms by a whole series of characters. The genus Cyiubiilia has therefore every 

 riirht to exist. 



The genus Cymbuliopsis was proposed by Pelseneer ^) to receive some forms, formerly 

 described as species of Cymbulia. Although the species of Cymbtiliopsis resemble Gleba more 

 than Cvmbulia (the name Cymbuliopsis therefore being not very well chosen), yet there are 

 some characters which justify the existence of Pelseneer's genus. 



The form for which the genus Desmoptcrus has been erected "), seemed to exhibit such 

 marked differences from any other "Pteropod", hitherto known, that the discoverer who regarded 

 his Dcsmoptertis papilio as a Gymnosomatous "Pteropod", established a new family Desmopteridae 

 for it. The description and figures, given by Chun, both of the external form of Dcsmoptertis 

 papilio and of its anatomy, support, however, strongly the belief that this species belongs to 

 the Cymbuliidae, an opinion, already expressed by Pelseneer *). I have had occasion to prove 

 the truth of the suggestion of this last author, as a species of Desmopferus was also found 

 in the Siboga-material (Stat. 169, West coast of New-Guinea). 



The only specimen (PI. III, figs. 80 — 81) very much resembles Desmopterns papilio, 

 but I have seen no pigment spots on the fins nor on the filiform appendages, which are rather 

 short. In every other respect this specimen is so very much like the animal of Chun that it 

 is recognised at hrst sight as a Desmopterus. 



As to the anatomy, after having made a series of transverse sections of the Siboga- 

 specimen, I agree with Chun in almost every respect. The radula, however, consists of three 

 longitudinal series of teeth ; in a transverse row, so there are three teeth ; this fact does not 

 correspond with the words of Chun") "etwa 20 — 30 Zahnchen sind in jeder Ouerreihe nach- 

 weisbar", and it procures an argument the more in favour of Pelseneer's opinion. It has 

 become obvious by the explanations of this last author : 



i) In DE Blainville, Manuel de Conchyliologie, p. 655. The few words of de Blainville are the only information we possess 

 about this species. 



2) Description of sixty new forms of MolUiscs., etc. Americ. Journ. Conch. vol. VII, p. 137. 



3) Challenger Report. LXV, p. 103. 



4) Nautilus III, p. 30—32, 1889. 



5) Ann. Mus. d'Hist. Nat. t. XV. p. 69, 1810. 



6) L. s. c. p. 100. 



7) Chun Bericht über eine nach den canarischen Insein ausgeführte Reise, Sitz. Ber. Berl. Akad., 1889, vol. III, p. 540 — 546. 



8) Sur la position systématique de Desmopterus papilio Chun, Zool. Anz., vol. XII, p. 525 — 526. 



9) L. c. p. 541- 



