39 



silken shroud preparatory to a winged flight, leaving to the world the record of a life well 

 spent — an unbroken thread of duty done : a treasury of silk to deck the sons of men 



" In courts, in feasts, and high solemnities." 



To grace man's outer life, and if in proper mood and contemplation, his inner life as well ; 

 for Nature's lessons are not learned under their external forms, but under the spiritual 

 beauty and verities they represent. 



" That not a natural flower can grow on earth 

 Without a flower upon the spiritual side, 

 Substantial, archetypal, all aglow 

 With blossoming causes — not so far away 

 That we, whose spirit-sense is somewhat cleared, 

 May not catch something of the bloom and breath. " 



Nature has many voices. She speaks to us in joyful song amid the activities of the day, 

 and in saddening dirges during the still hours of the night, while throughout her wide 

 domain, in song of life and dirge of death, she whispers Resurrection. 



Among the multifarious forms of insect-architecture, all of which are of absorbing 

 interest, I purpose at this time to record a few notes relating to the cocoons of the Bom- 

 bycidse. The cocoon made by the "Worm of the Orient has, from the circumstance that 

 its silk is so extensively used in manufacture, been fully described. This paper concerns 

 those of the Polyphemus, Cecropia, Cynthia, Luna and Promethea caterpillars, and it 

 may be regarded as an endeavour to foster an organized system of silk culture with these 

 worms, the Cynthia worm especially favouring cultivation, as it is double-brooded, and 

 since its introduction from the East, together with its food plant, the Ailanthus, it has 

 become largely distributed throughout the country. The habitat of some of these species 

 is co-extensive with the Union, and silk culturers are alike advantaged in every section of 

 the country with an abundance of food plant in our native trees. The silk produced by 

 them, though not of as fine a texture as that spun by the Mori Worm, is yet abundant 

 and of much greater strength. Notwithstanding the fact that the pointed end of the 

 cocoons of the Cecropia, Cynthia and Promethea worms is left open for the exit of the 

 moth, the threads are unbroken and the cocoons can be unwound. The Mori Worm 

 covers the interior lining of the cocoon with a gummy secretion, and when the moth 

 escapes, the threads, if not broken^ are thought to be in such danger that cultivators of 

 silk destroy the pupa before the period of emergence. There are entomologists, however, 

 who deny that the threads are broken at all, for they admit having succeeded in unwind- 

 ing cocoons from which the moths have escaped. The Cecropia, Cynthia, and Promethea 

 worms line each layer of silk, as well as the interior of the cocoon, with a gummy secre- 

 tion, leaving the silk at the exit opening free of agglutinating properties. This allows of 

 a ready escape of the imago without danger to the thread. If the cocoons of these worms 

 be divided lengthwise, and immersed in boiling water for a few seconds, a careful manipu- 

 lation will permit the separation of the several layers of silk, when, by the aid of a lens, 

 the life work of the caterpillar is beautifully presented and the continuity of the thread 

 can be discoverod. The exterior section of the cocoons of the Cecropia and Cynthia worms 

 can be easily divided into three layers of silk, while the interior portion is divisible into 

 six. The Luna and Polyphemus worms construct cocoons somewhat similar to the Mori 

 Worm, and as all parts of the interior lining are sealed, it becomes prudent, perhaps 

 necessary, to destroy the pupa. 



The Hairy Larvae and their Parasites. 



It is generally acknowledged by Entomologists that the hairy larvae, such as the 

 Arctians and their allies, very commonly escape parasitic attack, a circumstance attribut- 

 able to the fact, that in order to permit the deposit of ova, these caterpillars must be dis- 

 covered by the parasites in favourable postures, or else worried by them into such, that 

 the spines separating, give the only opportunity for the insertion of the ovipositor. This 

 was clearly demonstrated in an attack made by an Ichneumon upon a larva of Apatela 

 Americana Harris, which came under my observation in the early part of last autumn. 



