IOO MELANISM IN BOARMIA REPANDATA. 



Mr. I. Robinson, of The Wash, Hertford, thinks there may be 

 two other species. He has examined the gathering from Cautley 

 Spout near Sedbergh, and remarks : — ' Synedra amphicephala Kiitz. 

 S. famelica Kiitz., many. The two last-named are small forms 

 and difficult to identify, as the figures given in different works do not 

 quite closely agree. The latter forms are very numerous. . . I have 

 not found it noticed as a British species, but O'Meara gives several 

 habitats in Ireland for Synedra amphicephala Kiitz. ; his figure of it, 

 however, appears to be identical with Van Heurck's for S. famelica 

 Kiitz., so I cannot feel very positive as to the identification.' If 

 these two turn out to be the above-named species, they also will be 

 additional. Mr. Robinson also remarks : — ' Gomphonema ventri- 

 cosum Greg. There are many sporangial valves of this species 

 which are considerably larger than the normal forms ; these latter 

 are figured by Van Heurck (xxv. 15), and are named G. ventricosum 

 var. ornata Grun. They are, however, most clearly sporangial forms, 

 as I found several sporangia with the valves in situ before the 

 material was treated with acid. I do not know whether they have 

 been observed before, but I have seen no notice of them.' 



[The above list contains many rare and extremely critical species, 

 certain of which are so like commoner plants that very nice discretion 

 has to be exercised in their diagnosis, e.g., Penium mooreamim, Cos- 

 marii/m quadrum, C. quaternarium, and C. ochthodes, etc., and above 

 all, C. obliquum, the latter being one of the rarest Desmids yet 

 known. As to classification, the anomalies of chlorophyll arrange- 

 ment are such that, in our present state of knowledge, it would 

 perhaps be better to ' lump ' all the forms intermediate between 

 Cosmarium and Penium under Nageli's genus Dysphinctintn, rele- 

 gating those with perfectly cylindrical bodies and obsolete isthmi to 

 Penium. On this we would remark that the proposals of continental 

 botanists do not meet the anomalies referred to, and we think it 

 better to classify purely by affinity of form, until our knowledge is 

 vastly expanded. The observations of Archer in the Q. J. Mic. Sci., 

 1866, pp. 71 and 121, may be taken as dealing with the crucial 

 points of these distinctions, and, to this date, Archer's remarks have 

 not been controverted. — W.B. T.] 



NOTE—LEPIDOPTERA. 



Melanism in Boarmia repandata. — At the February meeting of the 

 Entomological Society of London, Mr. G. T. Porritt exhibited several melanic 

 specimens of this insect from Huddersfield, and — for comparison — two specimens 

 from the Hebrides. Mr. R. M'Lachlan remarked that melanism appeared to be 

 more prevalent in Yorkshire and the north midlands than in the more northern 

 latitudes of the United Kingdom. — H. Goss, Sec. Ent. Soc. Lond. 



Naturalist,. 



