140 BRITISH LEPIDOPTERA. 



Comparison of M. calthella with $ M. seppella. — The absence 

 of the silvery fascia? that characterise the male of M. seppella, makes 

 the female very similar to M. calthella. Bentley who first discovered 

 the similarity in Britain, unfortunately re-named M. calthella, calling 

 it sulcatella, and applied the name calthella to ? M . seppella. Although 

 there is a form of M. calthella without the purple base it rarely occurs in 

 this country (and we believe is equally rare in Germany), and hence, 

 perhaps, arises Stainton's distinction that the purple at the base of the 

 wing extends to the inner margin in 21. calthella, whereas in M. 

 seppella, it never reaches it. The former also is said to have (when dead) 

 a more sulcated appearance. 



Egg-laying.— The ovipositor is quite short, simple and tubular, 

 the egg is large and spherical, laid among moss. Chapman says that the 

 female,, when laying, creeps down among the moss to a depth of an 

 inch or more, and seems anxious to get to the bottom and lay her eggs 

 on the bottom of the jar, sand or earth. If the stratum be too deep 

 for this, she will lay them on a spray of the moss, always in little 

 groups, rarely as few as two or three, usually six to ten, and even 

 more, as many as twenty-five having been counted. The female will 

 often remain and die beside her last batch of eggs. 



Ovum. — The ova are spherical, 0-46mm. in diameter, almost white. 

 They have a snowy, mealy look, owing to the provision of a close 

 coating of minute rods standing vertically on the surface of the egg, 

 and often tipped with a small bulb (of fluid ?) ; whether these are 

 appressed to the surface of the egg when laid, or whether they after- 

 wards develop in some other way, I do not know, but I think the 

 latter. Their function would appear to be to protect the egg from too 

 close contact with the possibly very wet surface on which it lies 

 (Chapman). 



Habits of larva. — Chapman says° that about the middle of 

 August, 1892, he found several larvse about 1*5 mm. in length, and 

 though so much larger than when newly hatched, were otherwise 

 precisely the same in all respects. They were kept very wet, the moss 

 (Hypnum praelowjum) dripping, and the sand below under water, and 

 the result was decidedly satisfactory, as, at the end of September, the 

 moss was still growing, and the larvse usually to be seen. On 

 October 21st, there were three larvae in the jar, the two largest 

 measuring, with the head retracted, 8-5 mm. in length, and, 

 therefore, probably full-grown. About this time several were 

 found in another jar in which moss was growing, but which had 

 been kept much too dry ; these were only about 1*5 mm. long, 

 and another larva was found in another jar. At this time, 

 Chapman saw one of the larger larvae actually eating the delicate stem 

 of growing moss, of which a considerable piece of one side had dis- 

 appeared. The larvae seemed to be constantly on the move, at 

 times not to be seen, and when seen, always in a fresh place ; they 

 walk slowly but steadily, using the abdominal appendages as legs, and 

 often raising the fore part of the body and stretching about as if in 

 search of something. Judged by the sizes of their heads, there were at 

 least three stages of the larva on October 21st, which, with the newly- 

 hatched one, made four stages observed, although, no doubt, there 



* Trans. Ent. Soc. Loud., 1894, pp. 339 et seq. 



