32 



(c) A strange foe of leaf-eating caterpillars, and also of locusts and crickets — 

 which are also herbivorous, is the Hair-snake, Gordius varius Leidy. 



I have, preserved in spirits, two specimens of the same kind of leaf-eating 

 Lepidopterous larvae. One of them is plump and fresh coloured; the other, shriv- 

 elled and brown. From the latter, the long hair-snake that is with them extruded 

 itself. In life, the snake had been coiled, round and round, under the skin of its 

 host — and very close quarters it must have had there! It is a female of its 

 kind. In another \ial I have specimens of the larvae of one of the Tenthredinidae, 

 a Zaraea which feeds on the Buckbean, Menyanthes trifoliata L.— a swamp 

 plant. From one of the larvae, the male Gordius that is with them made its exit. 



The life history of the hair-snake is as yet incomplete. This much of it is 

 kno^Tii : — 



The female lays its eggs in a long chain which resembles a length of white 

 thread. She twists herself about this and holds it in place. In due time the eggs 

 hatch, and strange little creatures come from them. They are only l-4:50th part 

 of an inch long. At the head they have two circles of hooks, and with these they 

 work their way into the larvae of May-flies and Caddis-flies. In these they be- 

 come encisted. 



So much has been told us by Drs. Leidy and Meissner (Am. Ent. & Bot., Vol. 

 II., pp. 193-7). 



As in the case of the Trichinae, it is necessary for the young Gordii to pass 

 into a second host, that they may reach perfection. How they do so is a mystery. 

 It may be that when the Ephemera casts off its pseudimago dress it disburdens 

 itself of the encisted Gordii; and that these, faUing upon the herbage, are swal- 

 lowed by herbivorous insects. It is certain that myriads of destructive insects be- 

 come the prey of the Gordii. 



Professor Leidy made a careful examination of the egg-cord of one female 

 hair-snake, and found it to contain 6,624,800 eggs. 



But I must not take up more of your time. The instances I have given will 

 have afforded glimpses of the " wheels within wheels " in the grand machinery of 

 Nature — \^dll have afforded us an insight to the wise orderings of Providence, under 

 which all things continue as at this day. As we muse upon them, v/e are ready 

 to exclaim in the words of the Benedicite, omnia opera, " all ye works of the 

 Lord, bless ye the Lord: praise Him, and magnify Him forever." 



