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Mr. Sich exhibited sketches of several species of larvae, 

 illustrating the main characters of the various groups of the 

 Lepidoptera. 



Mr. McArthur exhibited two specimens of the extra- 

 ordinary S. American moth Thysania agrippina {strix), the 

 larger specimen measuring more than ten inches across the 

 expanded wings. Mr. Kaye said that he had seen the species 

 alive. It was accustomed to sit on the trunks of trees 

 with expanded wings, geometer-like, although it was really a 

 noctuid. 



Mr. Tutt then gave an address entitled, " Some Modern 

 Requirements in Oval and Larval Description," illustrating 

 his remarks by blackboard sketches and a large number of 

 diagrams, prepared by Mr. Bacot (see " Practical Hints for 

 the Field Lepidopterist," Part III, chapters 2 and 3). 



A considerable discussion ensued. Mr. Sich wished to 

 know if there was any hard and fast line between flat and 

 upright eggs, and instanced the egg, a species of Coleophora, 

 which had been described as belonging to opposite sections 

 by two observers. Dr. Chapman said that oval and larval 

 description was by no means an easy matter. In some in- 

 stances flat eggs simulated those of the upright section and 

 vice versci. As a fact, the two groups necessarily ran into 

 each other, and no definite line of demarcation could possibly 

 be made between upright and flat eggs, which would hold 

 good in every instance. Mr. Clark asked Mr. Tutt if he 

 could suggest the use of the complicated grouping of the 

 setse in larvae, and was answered in the negative. He also 

 noted that glycerine was a good medium for keeping material 

 for microscopical examination. Dr. Chapman said that for 

 permanent preservation no doubt some form of alcohol or 

 formalin was the better preservative, but as this hardened the 

 tissues it was much better to use glycerine as a temporary 

 preservative for material it was desired to examine. Mr. 

 Tonge wished to know the best way of using the micrometer 

 with the microscope, and several members were desirous of 

 similar information. Mr. Clark very kindly offered, later on, to 

 give a demonstration of the various methods of microscopical 

 measurement. Mr. Tutt replied, and stated that he had 

 expressly omitted to mention the difficulties of the subject. 

 He had only touched upon the main features of what was 

 required for scientific purposes, and again urged the members 

 to do more than merely photograph the ova and larva, to add 

 as close descriptions as possible on the lines he had detailed 

 in his address. 



