SOIjENOBIA UCHENEXXA, 175 



much. In spite of losing many larvae by various casualties, about 100 

 reached maturity, and these again produced, at the end of April, only 

 5 s, only six failing to emerge. The ? s laid as usual, and a month 

 later larvae appeared. The completion of the life cycle without presence 

 of the 3~ was thus demonstrated beyond possibility of error, &c. Speyer 

 later noted that he had never bred the male, nor did he know it. Von 

 Siebold notes (Stett. Ent. Zeit., xii., p. 343) S. Uchenclla as common 

 at Freiburg, in Breisgau, and describes it as "a wingless and sexless 

 nurse, with an ovipositor, and laying eggs sine coitu which produce 

 larvae." He further supposes it may be the " nurse " of a species of 

 Taleporia liable to alternation of generations, and adds that it is not 

 established that S. triquetrella (of which both sexes are known) is co- 

 specific with 8. lichenella, whilst the cases are very different, that 

 Uchenclla is found on old fences, about houses, in gardens, and trique- 

 trella (probably feeding on grass) crawling up trunks and rocks in the 

 woods to pupate. The cases of lichenella he describes as smaller and 

 darker than those of triquetrella, and considers there is a probability 

 that the sexuated and sexless individuals of a species may differ in 

 form, and that the parthenogenetic form may belong to more than one 

 species. There can be but little question that the 8. triquetrella (exc. $ ) 

 of Snellen van Vollenhoven (Sepp's Ned. Ins., ser. 2, iii., p. 233, pi. 42, 

 figs. 1-10) is to be referred here. His description, as well as his note 

 that the unfertilised females laid eggs that produced larvae, and that 

 only this form (without males) was known to the Dutch entomologists, 

 point to this conclusion. Steudel and Hofmann say that the partheno- 

 genetic form (lichenella, Z.) occurs in Wiirtemberg, on isolated plants, 

 and on walls, and produces only females ; their cases are usually covered 

 with yellow particles of lichen, and, therefore, look somewhat different. 

 Wocke says that in many places in Silesia only the parthenogenetic 

 form of the female is found. Peyerimhoff gives lichenella as common 

 on fences, tree-trunks, and walls, in Alsace. He follows Wocke in 

 calling it the parthenogenetic form of 8. pineti, and adds that it is 

 much more common than the ordinary male-producing form of the 

 latter. 



Egg-laying. — Hamm and Bacot both observe that the females (from 

 the Wellington College locality) commenced to lay eggs almost as soon 

 as they emerged, not really waiting for copulation. Both, too, observe 

 that though no males were obtained, and that although the females 

 were unfertilised, the eggs duly hatched. The eggs are laid inside the 

 larval case, from which the empty pupa-skin protrudes,, the ovipositor 

 being inserted between the latter and the edge of the case, whilst 

 mixed with them are hairs or wool from the anal tuft. The female 

 retains much of her bulk till the eggs are all laid, expanding herself 

 with air to replace the space previously occupied by the now deposited 

 eggs. Thi> is probably necessary to obtain proper fulcra for muscular 

 action. [Zeller notes that a large number of eggs that were laid by 

 an unfertilised $ in his possession, and referred by him to Uchenclla, 

 failed to batch, but formed empty wbite bladders of skin (looking 

 brownish-yellow against the light), placed irregularly, and apparently 

 contained nothing but air.] 



Ovum. — About -5mm. in length and ^mm. in width, oval in out- 

 line, slightly depressed on upper surface ; apparently a faint trace of 

 longitudinal striae ; slightly shiny, pearly-white in colour with a faint 



