ON THE REPRODUCTIVE ORGANS OF 

 HOLOZOA CYLINDRICA LESSON 



By Dr A. Arnbiick Christie-Linde 

 (Plate XXXII) 



IN the Magellan region Lesson (in 1830) collected a peculiar Polycitorid species of Ascidian which 

 he described under the name of Holozoa cylindrica. 



This find was long forgotten, and when several specimens were later collected in Antarctic waters, 

 this same species was described under different generic and specific names. This fact has been pointed 

 out by previous authors. Caiman's J/z/m/a australis and Herdman's Distaplia ignota, likewise Sluiter's 

 Julinia ignota, which have all been collected in the Antarctic, are no doubt representatives of Holozoa 

 cylindrica. 



With regard to the external form and shape of the colonies, as well as of the zooids, the previous 

 descriptions agree in essential points. I will return to a discussion of this matter in another paper, in 

 which additional conmients may be made. The reproductive organs only will be dealt with in this 

 preliminary note. 



The common view is that the colonies and the zooids in them are gonochoristic, i.e. either male or 

 female. But Caiman's statement (1895) as to this character is not quite clear. He writes: ' In all the 

 individuals examined several ova were found in various stages of development. . . ' (loc. cit. p. 10); 

 and further at the bottom of the same page : ' In nearly all the specimens examined hardly a trace of 

 testis could be found, although the vas deferens was usually full of spermatozoa. In one or two cases, 

 however, the testis was developed ' (p. 1 1). And further, on the same page : ' No definite relation between 

 the states of maturity of ovary and testis such as would suggest the occurrence of protandry or proto- 

 gyny could be demonstrated.' 



Michaelsen has pointed out that Herdman's Distaplia ignota is no doubt identical with H. cylindrica 

 Lesson, though he has accepted the generic name Julinia proposed by Caiman. He writes in his 

 description that the colonies of the species in question seem to be either male or female. 'Julinia 

 scheint wie Colella — getrennt geschlechtliche Kolonien zu produzieren' (1907, p. 41). 



Hartmeyer, too, is of the same opinion. He has had abundant material at his disposal, and the 

 result of his investigation is that the colonies examined by him are gonochoristic. 



With regard to Caiman's description Hartmeyer (191 1) remarks : ' Immerhin scheint mir nach allem, 

 was Caiman iiber die Geschlechtsorgane sagt, sein Material nicht giinstig genug gewesen zu sein, um 

 aus seinen Beobachtungen einen sicher begriindeten Einwand gegen die von Michaelsen und mir auf 

 Grund gewichtigen Tatsachenmaterials angenommene Eingeschlechtlichkeit der Kolonien her- 

 zuleiten' (loc. cit. p. 484). 



I now have reason to return to the subject, having had occasion to examine colonies of Holozoa 

 cylindrica collected by the Discovery Expeditions and also a few colonies brought back by the British 

 Graham Land Expedition (with the 'Penola'). The Discovery material was taken by dredge in the 

 mouth of East Cumberland Bay, South Georgia, 200-234 m. (St. 149), 10 January 1927, and that from 

 the British Graham Land Expedition was taken at Stella Creek, surface, 5 December 1935. 



The result of this investigation refutes the above-mentioned view of Hartmeyer and Michaelsen, 

 and gives proofs for an opinion opposite to that of these authors, for, as will be shown below, the species 

 in question prove to be hermaphrodite. 



