131 



ATLAS DER DIATOMACEEN-KUNDE. 



Since our last notice of this work, three more parts (6, 7, 8) 

 have been published. Part 6 is occupied by various forms of 

 Surirella (many of them new species), and as far as we have means 

 of judging by comparison with our examples, they are accurately 

 delineated, some of them particularly so. We especially note the 

 following: — S. elegans, E. {Campy lodlsciis elejans, Ralfs = ^S*. 

 slesvicensis, Grunow, S. alpina, Donkin), >S'. robusta {S. nobilis, 

 Smith), S. cardinalis, Kitton (this species is referred to S. guate- 

 malensis, Ehr., by Professor H. L. Smith and Herr Grunow ; accord- 

 ing to the former authority this species is also identical with S. 

 limosa, Bailey (not Brightwell). 



S, 2Jy''iformis, n. sp., Kitton, is a British species, first detected 

 in a gathering from the Firth of Tay, by Mr. Kattray, of Dundee. 



S. hastata = S. contorta, Kitton. Several very curious and 

 beautiful new forms, obtained from Demarara river mud, are figured 

 on plate 23, figure x. ; plate xxii. is not S. turgida of the Synopsis. 



Plate xxiv. contains some excellent figures of S. striatula from 

 various localities. 



The total number of forms figured in the six parts is 872. 



Part 7 contains 299 figures of Amphora, these, on the whole, 

 are not satisfactory ; they will, however, enable the student to 

 identify many species of this genus. 



Part 8, pi. xxix. is a continuation of PI. 1, and contains the fol- 

 lowing figures of Actinoptychi : — A. Pfitzeri, A. heterostrop>lms, A, 

 areolatus, A. boliviensis, A. hexagonus, A. Simbirskianus, A. sediic- 

 tilis, A. campanidifer. There are also several figures given, of 

 what the author terms " Regeneration valves " (our secondary 

 valves), he considers these to belong to A. areolatus. Mr. Roper 

 originally described these valves as a new species under the name 

 of A. hircidmtus, but a further examination of them, as occurring 

 in a gathering from Gorleston, Siifiulk (Herr Schmidt's drawings 

 are made from specimens found in this material), satisfied him that 

 they were portions of A. undulatus, of British observers. A. areo- 

 latus, as given in the " Atlas," seems to be only a more robust 

 state of figure 8, which the author calls an inner valve. 



In plates 30, 31, 32, we find 62 figures of species of that very 

 beautiful genus Auliscus, many of them very characteristic, but the 

 most skilful draughtsman is unable to do full justice to the exqui 

 site sculpturing of these tiny discs. No drawing has ever repre- 

 sented faithfully the beautiful markings on Auliscus racemosus, or 

 the parted appearance of A. pruinosus. The former species was 

 figured and sdescribed by Herr Janisch in his work on the micro- 

 scopic forms in guanos, under the name of A. Stockhardtii, and as 

 this is the older name, it must be retained. A good figure is given 

 of this species in the " Atlas," as is also of A. Grevillei, also 

 figured and described in the before-mentioned work. Whether 



