NOTES FROM SOCIETY'S NOTE-BOOKS. 251 



EXPLANATION OF PLITE XXIII. 



Fig. 1. — Mass of cocoons. 



,, 2. — Larvae inside of caterpillar. 



,, 3. — Larvae enlarged. 



^j 4 —Pupa of an Ichneumon (after Westwood). (These 4 illus- 

 trations taken from " Introduction to the Modern Classifica- 

 tion of Insects," Vol. II., p. 148, Fig. 76.) 



,, 5. — Mass of cocoons deposited in the autumn of 1877. (West- 

 wood's figure represents them as too regularly arranged. I 

 find them heaped together in all sorts of positions, like a lot 

 of tired children that have tumbled down together after play 

 and fallen dead asleep, no matter how or on whom they fell.) 



,, 6. — Cocoon in its entire state. 



,, 7.— One from which the Ichneumon has recently made its exit ; 

 the end cut off remains like a lid to the " win " (cocoon). 



,, 8. — Microgaster glomeratiis, Imago. 



Selected) IRotee from tbe Societij'e 



Calcareous Nodule from Coal.— This was taken from a seam 

 of coal worked about Oldham. These nodules are full of the 

 remains of the vegetation which flourished so luxuriantly during 

 the formation of our coal-seams. The section enclosed is cut 

 transversely, and shows three or four forms of Rachiopteris, several 

 of which have been described in a memoir of the Royal Society, 

 read March 25th, 1874, by Prof. W. C. Williamson. These ferns 

 will vie with any recent ones in the peculiar arrangement of the 

 vascular bundles. J. Butterworth. 



Fin of Flying-Fish.- Exoccetus evola?is is a tropical species and 

 not identical with that occasionally found in the Mediterranean 

 {E, volitans). There are, however, I believe, many more species, 

 though not many of them have been described. The membrane 

 of the pectoral fin, or wing, is in some parts strongly marked with 

 star-like spots, whilst in other parts the fin-marks entirely disap- 

 pear. The fin-rays polarise tolerably well. The fish, when 

 alarmed, leaps from the water and skims along, perhaps 100 or 

 200 yards, seldom rising more than a foot or two above the 

 water, the wings vibrating rapidly all the time. Such, at least, is 

 my impression, though some writers have asserted that they only 

 act as a sort of parachute, and that the force of the jump alone 

 propels the fish. This may be the case with some species, but I 

 am certain that this species remains on the fin for a considerable 



