352 INSECTA. 



Some have but fifteen pairs of feet *, and their body viewed from 

 above presents fewer segments than when seen from beneath. 



SCUTIGERA, Lam. CERMATIA, Illig. 



The body covered with eight scutelliform plates, under each of 

 which M. Marcel de Serres has observed two pneumatic sacs or vesi- 

 cular tracheae, which receive air and communicate with lateral and 

 inferior tubular tracheae. The under part of the body is divided into 

 fifteen semi-annuli, each bearing a pair of feet, terminated by a very 

 long slender^multi-articulated tarsus ; the last pairs are more elonga- 

 ted ; the eyes large and compound. 



Their antennae are slender and tolerably long ; the two palpi sali- 

 ent and furnished with small spines. The body is shorter than in 

 the other genera of the same family, and the joints of their feet are 

 proportionably longer. 



The Scutigerse, which by these characters form the passage from 

 the preceding family to the present one, are extremely agile animals, 

 and frequently part with some of their feet when seized. 



The species found in France f conceals itself between the 

 beams and rafters of houses. 



LITHOBIUS, Leach. 



The stigmata lateral ; body divided above and beneath into a simi- 

 lar number of segments, each bearing a pair of feet; the superior 

 plates alternately longer and shorter, and overlapping each other 

 close to the extremity. 



L. forficatus; Scolopendra forficata, L. ; Fab., De Geer; 

 Geoff., Hist, des Insect., II, xxii, 3; Panz., Faun. Insect. Germ., 

 L., xiii; Leach, Zool. Miscel., cxxxvii J. 



The others have a least twenty-one pairs of feet, and the segments 

 both above and underneath are equal in size and number. 



SCOLOPENDRA, Lin. 



Those which form the two feet that immediately follow the two 

 hooks forming the exterior lip, presented but twenty-one pairs, and 

 whose antennae have seventeen joints, constituting the genera Scolo- 

 pendra and Crytops of Leach. There are eight distinct eyes, four 

 on each side in the first, and that in which the largest species are 

 found ; in the second, they are null or but very slightly visible. 



The most southern departments of France and other countries 

 of the south of Europe, produce a species Scolopendra cingu- 



* Dr. Leach makes two pairs more by including the palpi and the hook-like feet 

 of the head. 



f The Scolopendre it vingt-huit pattes of Geoffroy which appears to differ from the 

 the S. coleoptrata, Panz., Faun. Insect. Germ., L, xii, and from that of Linnaeus; 

 lulus araneoides, Pall., Spicil. Zool., IX, iv, 16; Scolopendra longicornis, Fab., of 

 Tranquebar. See also Leach, Zool. Miscell., Cermatia livida, CXXXVI, and Lin. 

 Trans. XIV. 



I L. varieyatus, lavilubrum, Leach, Lin. Trans., XI. See also vol. III. of his 

 Zoological Miscellany. 



