412 Rev. T. Blackburn on Haicaiian Neuroptera. 



brilliant purple (" Selipurpur ") in the sensitive apparatus of 

 the retina of some animals, particularly the lizard. When 

 the Gyanea is placed in a glass aquarium this colour fades in 

 less than an hour to a dirty brick-red. When the Medusa is 

 sick, even in the open sea, it is always this colour which is 

 affected first, and turns into a dirty coffee-colour long before 

 the tentacles begin to drop off, which is always a sign of 

 approaching death. 



In my paper on the structure of Cycinea annashala I pointed 

 out that no pigment occurs in the marginal bodies, and that 

 therefore the organs of sight of this species, if to be found in 

 the marginal bodies at all, were not nearly so highly deve- 

 loped as in the other Medusa?, or even as in other species of 

 the same genus which do not possess purple mouth-arms. 



Sensitive cells are very numerous, particularly in the purple 

 margin, and contain the purple substance. Ganglion-cells are 

 also met with there. The pigment in the other parts might 

 be considered as reserve material for that which may perhaps 

 be used up by the sensitive cells. I do not go so far as to 

 draw the conclusion which the reader will have inferred from 

 the preceding lines ; but I should like to hint at the possibility 

 of the mouth-arms of our Medusa being able to perceive light. 



LII. — Notes on Hawaiian Neuroptera^ with Descriptions of new 



Species. By the E,ev. Thomas Blackbukn, M.A. 

 Some years ago I sent a small collection of Hawaiian species 

 of this order to Mr. McLachlan, concerning which a remark- 

 ably interesting paper from that gentleman's pen appeared 

 in the Ann. & Mag. Nat. Hist, for October and November 

 1883. It was at the time a matter of much regret to me that 

 the number of specimens I was able to send Mr. McLachlan 

 was very meagre, owing, 1 think, to the fact that the Neu- 

 roptera occupy only a secondary place in my studies, rather 

 than to their being of rare occurrence on the archipelago. 

 Since the appearance of the above-mentioned paper my scanty 

 leisure time has been devoted to describing new Hawaiian 

 (voleoptera ; but as that work is now completed (so far as my 

 materials go), 1 think it might not be without interest if 1 

 were to pass in review the results of my exploration, not 

 hitherto published, in the other orders. In doing so 1 shall 

 not attempt to name and describe species, except where they 

 happen to have very salient characters, but shall content myself 

 with indicating their affinities in general terms, leaving their 

 more precise disposal for the possibilities of the future. I pro- 



