52 SUMMARY OF OUEKENT RESEARCHES RELATIKG TO 



8. Some, if not all, of the parenchymatous cells are in connection 

 with fine nerve-ramules. 



7. The luminous organs are, morphologically, equivalent to the 

 fat-body. 



The author's most successful preparations were made with osmic 

 acid, living and luminous specimens being placed in 0* 1 to 1 per cent, 

 solutions, or were subjected to its vapour ; after washing with dis- 

 tilled water they were placed in alcohol or in a mixture of alcohol 

 and glycerine. Good preparations were obtained by colouring with 

 haematoxylin or picrocai-mine, or by the methyl-green solution 

 recommended by Mayzel and Strasbui'ger. 



It is of interest to observe that the author thinks that the layer of 

 cells free from uric acid may become converted into an uric-acid 

 series ; and he bases this suggestion on the fact that the boundary 

 line between the two is very irregular, and that the cells of the one 

 set often project into the other ; there is, too, a very considerable 

 variation in the thickness, the dorsal being in some specimens much 

 thicker than the ventral, and vice versa. Physiological evidence is, 

 however, still wanting to complete the proof. 



The characters of the lateral limainous knobs found in the female 

 of Lampyris splendidula are discussed, and it is pointed out that they 

 occupy the only position in which it would be possible for their light 

 to pass upwards and sideways ; the organs of the larvte of this species 

 are distinguished from those of L. noctiluca by not being confined to 

 one segment of the body, but existing over the whole of the abdomen ; 

 in structure they appear to be similar to those of the female, but they 

 are smaller in size. 



The adult species of Lampyris appears to be characterized by the 

 frequent presence of organs which, in other Insects, are only found in 

 the larvae ; as examples, we may cite the tracheal end-cells, and the 

 large cells which lie almost freely in the body-cavity, instead of being 

 united with tissues ; so again in the fine, transversely-striated muscular 

 fibres of the female of L. splendidula we find one or two large, clear, 

 semilunar swellings, with granular contents and a large nucleus; 

 these cannot be regarded as anything else than the remnants of the 

 embryonic formative cells, from which the muscles have been differ- 

 entiated. Yet again, the soft and wingless females are externally but 

 little more highly developed than the larvae. It cannot be doubted 

 that the luminous power is a secondary sexual character, and its 

 possession by the larvae is perhaps to be explained by their poisonous 

 nature, so that they warn the insects that might attack them. 



/3. Myriopoda. 



Existence of a Blastopore and Origin of the Mesoblast in 

 Peripatus.* — The late Professor F. M. Balfour was just before his 

 death engaged in the preparation of a monograph on the anatomy and 

 development of the members of the genus Peripatus, together with 

 an account of all known species, and he left a series of notes, com- 



♦ Proc. Roy. Soc, xxxiv. (1883) pp. 390-3. Cf. Natiue, xxvii. (1882) p. 215. 



