Professor Askenasy's results as to the presence of both chlorophyll grains and starch in all 

 parts of the joints. Of the nuclei and cytoplasm I can say nothing at present and can only 

 hope that good material may soon be obtained on which to work out the details of the cell-contents. 



Fruit. References to the literature bearing on the fructification are given in the historical 

 summary above. 



In this summary, reference to Professor Schmitz' paper "Die Bildung der Sporangien bei 

 der Algengattung Halimeda" (Sitzungsber. d. Nied. rhein. Gesellsch. Bonn. 14 Juni 1880. p. 

 140) has been inadvertently omitted. He describes at some length his observations on the 

 fructification of H. Titna and H. platydisca. For the sake of comparison with H. Tuna, he 

 refers to a figure by Zanardini (Icon. Phyc. Adriat. et Medit. vol. III. tab. CXII. 1871) of a fertile 

 plant of H. macroloöa, but the figure in question is described by Zanardini as that of H. 'Tuna; 

 so that the contrast drawn by Professor Schmitz must be considerecl valueiess. 



Up to the present time sporangia have only been described on H. Tuna, H. platydisca 

 and H. macroloöa. The filaments of the central strand appear to grow out from the margin 

 or from the face of a joint and bear small globose or obovate bodies on short stalks, 

 which contain the zoospores. A description of these zoospores after they have escaped 

 from the sporangium is given by MM. Derbés et Solier 1. c. p. 47. "C'est toujours une 

 portion postérieure, arrondie, de couleur verte, et une portion antérieure conique, hyaline. Le 

 rostre nous a paru quelquefois prendre une longeur, une extension relativement très-considérable. 

 Nous avons apercu plusieurs fois, très-distinctement, deux appendices flagelliformes partant du 

 sommet du rostre, et un autre attaché a la partie postérieure ; d'autres fois, ce dernier manquait. 

 Chez d'autres, il n'en paraissait qu'un seul au sommet du rostre, et très-souvent nous n'avons 

 pu en apercevoir aucun, soit en avant, soit en arrière. Quant aux mouvements, ces zoospores 

 sont tout-a-fait comparables aux autres. Nous n'avons pu obtenir ni depots ni germinations". 



These authors do not mention any sign of conjugation. It is much to be desired that 

 further investigation on the fructification of the various species of this genus could be carried 

 out on living material. 



Geographical Distribution. Halimeda flourishes principally within the tropical zone, but 

 is not confined to it ; for H. Tuna is a fairly cominon plant in the Mediterranean and Adriatic, 

 reaching as far N. as 45 1 / 3 ° N. Lat., while H. cuneata descends as far as to 32 S. Lat. on 

 the West coast of Australia and to 34° S. Lat. on the East coast of S. Africa. 



By some extraordinary chance 110 less than three species of Halimeda are recorded in 

 literature from Kamtschatka : H. discoidea Decne, H. multicaulis in Kützing's Species Algarum 

 p. 504 and H. cuneata Hering in Kützing Tab. Phyc. vol, vu. p. 8. where the detail "Süd- 

 spitze von Kamtschatka" is addecl. I have seen in the Kützing Herbarium the original plant 

 of "ƒƒ. cuneata" here figured and find it is H. gracilis, which is confined to the tropics. The 

 Decaisne specimen of H. discoidea, which I have also seen, bears the inscription : "Kamtschatka, 

 Voyage de la Vénus". It can only be supposed that these plants were drifted to the north In- 

 the Japan current and were picked up by the various collectors ; for the temperature of the 

 sea round the coasts of Kamtschatka would not allow of the growth of any species of Halimeda. 



Another unlikely record is that made by Dr. Fleming in his "History of British Animals", 



