May iS 1882] 



NA TURE 



the total eclipse of 187S — duly chronicled in the Daily 

 News at the time — was one by which Prof. Newcomb 

 demonstrated a tremendous extension of the corona in 

 the direction of the plane of the sun's equator, or very 

 near it. It will be important to see, whether on the pre- 

 sent occasion the extension will be so great, especially 

 since Dr. Siemens has thrown down the gauntlet to astro- 

 nomers by his bold speculations touching the circulation 

 of the solar gases. Such, then, are some of the things 

 which the Eclipse Expedition is going to do, or going to 

 try to do. If all goes well, I shall be able in my next 

 letter to tell your readers something of a definite nature 

 as to the actual camping-ground and the local arrange- 

 ments in Egypt. 



The following telegram from its special correspondent 

 is given in Tuesday's Daily News : — 



Sohag, Monday 



The preparations are complete for the eclipse on Wed- 

 nesday, thanks to the assistance rendered by the repre- 

 sentatives of the Egyptian Government to the English, 

 French, and Italian observers alike. The weather is 

 apparently settled. There is little probability of dust- 

 storms. The greatest heat experienced is 108 in the 

 shade. The temperature is now cooler. The English 

 Baity will probably return by Carthage, leaving Suez on 

 the 31st. 



ALG/£ X 

 I T is little more than a year since the Latin edition of Dr. 

 ■*■ Agardh's work on the " Morphology of the Florideae" 

 was noticed in the pages of Nature. The author now 

 sends us another contribution to the systematical study of 

 algae. The present is, however, not a distinct work, but 

 a continuation of a series of Essays or Monographs, the 

 first instalment of which appeared in vol. ix. of the Tran- 

 sactions of the University of Lund, in the year 1872. 

 The subjects of the first instalment were the genera 

 Caulerpa and Zonaria, and the classification and de- 

 scription of the Australian species of certain tribes of 

 Sargassum. 



The present work consists of essays on the CHOR- 

 darie.k, and on some of the DlCTYOTE.E. Although it 

 bears a Swedish title, it is written in Latin. It com- 

 mences with a monograph of the family Chordarieae, 

 which is entirely reconstructed, and is enlarged by the 

 introduction of several new genera. Under the present 

 arrangement it comprises seventeen genera. 



From the increa-ed activity recently shown by British 

 algologists whose exertions have been rewarded by the 

 discovery or many species of Alga; new to these shores, 

 it would seem desirable to mention more particularly a 

 few of the changes which have been made in the present 

 work by Dr. Agardh in the classification of some of the 

 plants of the olive series of Algae. 



Beginning with Elachi^tea, as the author, restoring 

 the old spelling, prefers to call it, we find that this genus 

 is removed to the CHORDARIE.*:. This is in accordance 

 with the views of Dr. W. H. Harvey, expressed in the 

 "Phje. Brit. Tit." E.fucicola. This genus is especially 

 interesting from the fact that out of the nine species, 

 seven are British. E. velutina (of the " Phj-c. Brit." pi. 

 xxviii. B), removed by Thuret to Streblonema, is placed 

 by Dr. Agardh in his new genus Herponema (see p. 55). 



The next genus, Myriocladia, includes M. Loveni, an 

 extremely rare species, which has been obtained grow- 

 ing on oysters in deep water in the Baltic, and which Dr. 

 Agardh (" Sp. Alg.", p. 53) states was found by the late 

 Mr. Borrer on the Sussex coast ; it has not, however, 

 been met with b) succeeding observers ; neither has Dr. 

 Agardh seen the plant in other collections. The name 

 of this rare plant does not occur in the published lists of 



I -rncs Systemalik. Nya bidrag af J. G. Agardh (Andra Afdel- 

 ninjen) Lunds Univ. Arsskrift. Tom. xvii. (mo., pp. 134). 



Algae found by Mr. Borrer. A representation, much 

 enlarged, of some of the details of the plant, will be found 

 on PI. 1, Fig. 3. 



The genus Mesogloia is now restricted to two species. 

 M. Mediterranca and M. vermicularis. M. virescens is 

 removed to Eudesme, of which another species inhabits 

 Tasmania and South Australia. Chordaria divaricate 

 and Mesogloia Giijfithsiana are now respectively Cas- 

 tagnea diva ricata and C. Grijjitlisiana. The observations 

 on the structure and fruit of the epiphytic plants, which 

 constitute the genera Myrionema and Herponema, will 

 be interesting to British algologists. 



Among the new Algae which have been recently added 

 to the British Marine Flora, is the handsome plant found 

 by Mr. G. W. Traill, in the Firth of Forth, and issued to 

 British collectors under the name of Dictyosiphon Hippu- 

 roides. The plant was first described and figured by 

 Lyngbye in the " Hydrophytologiae Danicae," under the 

 name of Scytosipkon Hippuroides ; then, in Agardh's 

 " Sp. Gen. et ord. Alg.", vol. i. p. 66, as Chordaria flagel- 

 liformis, var. D. Hippuroides. Areschoug subsequently 

 distributed dried specimens of the plant, and published 

 (Sot. Notiser, 1S73, No. 6., and Obs. Pkycol., iii. 1S75) de- 

 scriptions of it underthe name of Dictyosiphon Hippuroides. 

 In the present worn Dr. Agardh maintains the opinion he 

 had expressed in 'Sp. Alg." more than thirty-three years 

 ago, that the Scyt. hippuroides of Lyngbye is a form of 

 Chord, flagelliformis, and not a Dicnosiphon. He sup- 

 ports his views by a minute description of the structure 

 of the frond, and gives at length (pp. 67-70) his reasons 

 for differing in opinion from his old friend Dr. Areschong. 

 As a proof of the care with which Dr. Agardh conducted 

 his examination of the plant, it may be mentioned that 

 he describes and names six forms of it, including among 

 them, Scyt. Hippuroides, LI., and Scyt. tomentosus or 

 Fl. Dan. and Lyngb. British algologists will find this 

 part of Dr. Agardh's work particularly interesting. 



Among the Alga; which have been recently added to 

 the British Marine flora are Ph/aospora torti'lis (Rupi 

 Aresc, and Diet. \ Coilonema) mesogloia, Aresc. ; it may he 

 mentioned incidentally that Dr. Agardh considers botii 

 Phlaeospora and Coilonema as distinct genera. 



The DlCTYOTE/E. — The author commences with pre 

 liminarv remarks on the limits of the family, and the struc- 

 ture and fructification of the different genera (pp. 77-S3). 

 Then follows an elaborate essay on the genus Dictyota 

 (pp. S3-92) : and after that a description of the species, 

 and the tribes under which they are arranged. Of the 

 twenty-six species, one only, D.'dichotoma, is a native of 

 our shores. Six other species are referred to Dilophus, 

 J. Ag , and two to Glossophora, J. Ag. 



The genus Spatoglossum, Kg., includes Tao/tia Solicrr', 

 T. Sckraederi, and two others. Then follow a few 

 observations on Taenia atomaria. Padina is treated at 

 greater length. To this succeed elaborate observations 

 on the structure and fructification of Zonaria (pp. 120- 

 131), and some remarks on certain species. This part o( 

 the work, it must be observed, is supplementary to the 

 article on Zonaria in the first part of the " Bidrag," p. 45. 

 before referred to, in which the several species are 

 described. 



It may here be remarked that the Zonaria eollaris ot 

 the " Phyc. Brit." has no claim to be considered as a 

 native of the British Isles. It is found in the Mediter- 

 ranean and Adriatic, and occasionally in Granville Bay, 

 on the French coast. It is not a Zonaria, but a Cutleria. 



The work concludes with some observations on the 

 species of Halyseris. 



In the selection of the preceding subjects for remark, 

 the writer has been guided by the interest which, it was 

 thought, would be taken in them by British algologists ; 

 it'must. however, be observed that the work has also 

 many points of interest as regards Australia, Tasmania, 

 and New Zealand. Among the species belonging to the 



