with particular regard to the Danish Fauna. 193 



The antennas of the Prioni appear quite bald when examined 

 by the naked eye or by a glass of moderate power ; they may be 

 knotty and thorny, but on the very long forms of antennas not a 

 single hair is to be discovered ; and on the short ones (Parandra, 

 Spondylis) there are only isolated short stiff bristles, but not the 

 close fine covering of hairs which is observed in other Cerambyces. 

 Besides, the surface, at least of the last joints, is either dull or 

 shows interferential colours all over or on some circumscribed 

 spots, being covered with innumerable minute holes. By a 

 proper preparation (for instance, by boiling a piece of an 

 antenna well for a couple of minutes, and then making deli- 

 cate longitudinal and transverse sections with a very thin knife), 

 the microscope will show that these holes are cauldron-shaped 

 depressions, carrying at their bottom a very short pellucid hair, 

 whilst for the rest the envelope of the antennas shows the 

 ordinary structure of the external envelope of Arthropoda, viz. 

 a great many layers of chitine, which from the inside are perfo- 

 rated by the roots of the hairs which, had begun to grow out 

 before those layers were formed. 



This description of holes, in which the hair at the bottom is 

 invisible except by means of a strong lens, so that the surface 

 appears bald, I propose to name pores ; they are found on the 

 under surface of the antennas, from the third to the eleventh 

 joints, grouped in various ways, which will afford an excellent 

 material for the circumscription and definition of genera. These 

 arrangements may, as far as I have hitherto observed, be de- 

 scribed as " poriferous spots" or "poriferous depressions, 

 canals, pore-nets," &c. (areae, foveas, foveolas, canalicular, &c, 

 poriferas), and others, of which the following instances may be 

 mentioned : — 



Spondylis. — An oblong, somewhat depressed, poriferous spot on 



each joint. 

 Thaumasus. — A small, deep, irregular depression on each joint. 



pores and short hairs. In others of the same family (Epiphysa, Pkyso- 

 sterna, Adesmia, Zopherus, Eurychora, Morica, Akis, Scotobius, Asida, 

 &c.) the pores are furnished with a short felt, and grouped in sharply cir- 

 cumscribed spots and diamonds on the last joints of the antennse. In 

 Scaurus these joints are entirely covered with large short-haired pores; 

 and analogous though somewhat different arrangements are to be ob- 

 served in Nyctobates and allied genera. Helops and many other genera 

 have the last joints quite covered with minute hairs, no pores at all being 

 visible outside. The arrangement in Diajieris, Uloma, and other genera 

 with moniliform antenna?, is very remarkable — the ends of the joints, 

 sometimes also their sides, being occupied by pores of enormous size, 

 closely and regularly placed. These few cursory indications may suffice in 

 order to procure for this phenomenon the attention it deserves. 



Ann. $ Mag. N. Hist. Ser. 3. Vol. xv. 13 



