264 



SCIEXCE- GOSSIP. 



of less close tissue, composed of stronger and 

 longer threads placed parallel. 'Ibis upper tent 

 was closed on one side, but always open on the 

 other : and Huber thought it might serve as a 

 place of refuge for the mother. He mentions that 

 the species with spotted wings always made for its 

 own residence a sort of web composed of long 

 parallel threads. Some of the individuals which 

 thus lurked under a trellis of silk were believed to 

 be males. The creatures had space beneath their 

 coverings to move about a Little, and they could 

 easily escape when they wished to do so. Accord- 

 ing to McCook. Psoeus partis in America makes a 

 tubular tent-like web in crevices of bark, etc. 

 Under this web the insect Lives after the manner 

 of a tube-weaving spider, and entomologists who 

 wish to capture it have to push it out by pressing 

 upon the tent ( s ). As to the purpose of these 

 webs, Huber thinks that the Lines may serve to 

 warn the creature of the approach of enemies ; but 

 not to protect it from attack, for the tents were so 

 frail that a gnat might aLmost break them. Lt is 

 certain, he adds, that Psocids do not lie in 

 ambuscade Like spiders, for they are not preda- 

 ceous. 



With regard to the position of the spinning- 

 organs, Huber has made it clear that the threads 

 come from the mouth. He was at considerabie 

 pains in attempting to establish their exact source, 

 but found observation difficult on account of the 

 smaiLness of the flies and the rapidity of their 

 movements. After placing some of the insects in 

 glass tubes and following them with a strong lens, 

 he was incLined to beLieve that the silk proceeded 

 from the upper lip (labrum). Hagen, however, who 

 examined the Labrum. found no spinning-organ 

 there, and he suggests that it is probably situated 

 'in the tongue (hypopharynx). a structure asso- 

 ciated with the lower lip (labium). Burgess has 

 since found within the tongue a pair of peculiar 

 organs — Lingual glands, which open by a common 

 duct into the mouth near the throat ( 9 ) : and these 

 are thought to be concerned with the spinning 

 work ( 10 ). 



VIII. — Embiids. 



Other spinning imagines are found in the familv 

 Embiidae. also Pseudo-neuroptera. a small eroup 

 of insects of moderate size, of no popularity, and 

 imperfectly known even to entomologists ("). The 

 creatures are said to be related in certain respects 

 to Psocids; but they are dissimilar, having per- 

 haps a slight resemblance to Termitids. or white 

 ants, with which aLso they are supposed to have 

 some relation ship. 



The spinning facuity, though occurring in the 

 perfect insect, is better known in the larva : and it 



(8) McCook, i.e. 



(9) E. Burgess, Anatomy of the Head, etc., in the Psocidae, 

 Proc. Boston Soc. of Nat Hist., xix. (1878), pp. 291-6. 



(10) Sharp, I.e. 



<11) Sharp, torn. cil.. pp. 351-5. 



has been observed, further, in a form regarded by 

 M-Lachlan as the nymph. The precise period at 

 which it is noted, however, is not of great import- 

 ance, for there is no marked metamorphosis, the 

 insect having much the same form throughout Life. 

 Lucas states that the Larvae of Embia maxuritanica 

 are found under stones in small silken tunnels : 

 and similarly those of E. solieri are stated by 

 Lucas and by Girard to be found in similar situa- 

 tions also in tunnels of silk. A box in which some 

 of the larvae of the first-named species had been 

 placed in 1850 was forgotten till 1858, and when 

 opened was found to have its waLLs clothed with 

 fine white silk, forming circular tunnels, in which 

 dead larvae were lying ( 12 ). Another Embiid. Oligo- 

 toma michaeli, found chiefly in a wingless, perhaps 

 larval, condition ina hothouse among orchids, was ob- 

 served by Mr. Michael to have made a large number 

 of webs on the roots and stems of the orchids and 

 of neighbouring plants ( 13 ). These webs had the 

 form of silken galleries. They were not perfect 

 tubes, but more of the nature of coverings, protect- 

 ing the creatures from above and permitting them 

 to feed upon the surface of the plant on which the 

 web rested ( u ). One individual spun a web on the 

 side of a box in which it had been confined for two 

 hours ( 15 ). and some time afterwards the web had 

 been so much extended that it attached the lid to 

 the box. When the Lid was removed the insect ran 

 about with activity. •• ever and anon retreating 

 into a small, loose silken den or tunnel it had 

 woven for itself at the bottom of the box " ( l6 ). A 

 figure of this individual shows small undeveloped 

 wings, so that it had perhaps passed the larval 

 condition. M-Lachlan states that silken tunnels 

 were spun by nymphs as well as larvae of this 

 species : but it has been suggested that the form 

 regarded as the nymph may have been the adult 

 short-winged female ( 17 ). 



It is in Embia latreUlii= Oligotuma saiindersii 

 that spinning is definitely recorded for the perfect 

 insect. According to Lucas, both winged and 

 wingless individuals of this species were found in 

 silken galleries about the base of leaves of a 

 Cycas (from Madagascar), the silk being woven by 

 the winged perfect insects as well as by the wing- 

 less larvae. 



It has been supposed that the threads come, as in 

 Psocus, from the mouth : and it has even been 

 said that spinning organs open on the Labium ( iS ). 

 Michael saw Oligotoma michaeli making its web 

 apparently " with some organ situate in or near 



(12) H. Lucas, quoted by Hagen, Monograph of the Embidina. 

 Canadian Entomologist, xvii. (1885), pp. 1-11-206. 



(13) W. H. Michael, Gardeners' Chronicle (n.s.), vi. (1876), 

 p. 845. 



(14) M'Laehlan, Journ. Lin. Soc., Z00L, Tiii. (1878), pp. 273- 

 84. 



(15) Michael, l.c. 



(16) W.G-. S., The Web of the Embia, Gardeners' Chronicle 

 1 OJS. 1. vii. (1877), p. 50. 



(17) Hagen, he. : Sharp, I.e. 



( 1 8) Hagen, l.c. 



