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scribed by him as present in the whole group of genera allied 

 to Phasma (s. str.). They are very conspicuous in Autolyea 

 pallidicornis Stal, and doubtless all the species possessing the 

 foramina are endowed with this peculiar means of defense, the 

 only one known to Phasmidae, apart from their mimetic deceits. 

 It may be questioned, indeed, whether the foramina are not 

 common to the entire family, for they occur also in Phyllium 

 and Heteropteryx and all other genera I have examined, even 

 in those not appertaining to the groups in which they are men- 

 tioned by Stal. In Heteropteryx they are conspicuous and are 

 situated at the outer anterior base of a large pointed spine, in 

 the same relative position as in the genera already mentioned. 



The occurrence of foramina repugnatoria presupposes, of 

 course, some tegumentary follicles or deeper seated glands for 

 the secretion of the offensive fluid, and since the existence of 

 glands of any considerable size, opening upon the sides of the 

 body, is quite unknown in the true insects, as far as I am 

 aware (with the exception of such extensible structures as the 

 caruncles of Malachius and allies), it is additionally interesting 

 to observe that these foramina are the openings of true gland- 

 ular odorifersB, which, in certain species, attain a very great size. 

 If an Autolyea pallidicornis, for instance, be opened upon the 

 dorsal surface, 1 these glands will be seen at first glance lying 

 side by side above the salivary glands, — two straight, flattened, 

 ribbon-like bodies, blind sacs with stout walls, each one and a 

 half millimetres broad, extending from the posterior extrem- 

 ity of the mesothorax, where they are broadly rounded, to 

 the anterior part of the prothorax ; here they are curved 

 slightly outward toward the foramina and taper rapidly, chang- 

 ing at the same time from a flattened to a cylindrical, and finally 

 to a compressed form, so as to have the appearance of being 

 twisted through quarter of a circle. The membrane at the base 

 of the pit in which the foramina are situated is very delicate, ex- 

 cepting near the centre, where it is thickened ; in the middle of 

 the thickened portion occurs a nearly perpendicular slit, less than 

 0.25 mm. long, which may probably be opened or closed at will 

 by the action of muscles on its thickened walls. In Aniso- 



*A11 my observations are taken from specimens preserved in alcohol. 



