302 DESCRIPTION OF THE PLATES. 



When the mouth-parts are at rest the tongue is partially retracted, 

 and together with the labral palpi and laciniae of the maxillae are recurved 

 within the mouth. The sub-mentum, lora, and cardines of the maxilla 

 are folded upon one another at the same time and hidden by the large 

 mentum. 



Briant, J. L. S. xvii. 1884. 



Cook, Amer. Naturalist, xiv. 1880. 



FIGS. 6-9. Appendages connected with the mouth, and Fig. 10, the first pair of ambulatory 

 limbs of Scolopendra morsitans, after Savigny, Memoires sur les Animaux sans vertebres, Part I, 

 Paris, 1816. Slightly altered from a specimen. 



6. Mandible : a. small three-jointed palp. 



7. Maxilla, consisting of a small soft external * palp ' and a median lobe 



which, as in Myriapoda Diplopoda, e. g. lulus, is fused basally with 

 its fellow. 



8. Palp-like limb. In Scolopendra audax^ according to Pagenstecher 



(Allgemeine Zoologie, ii. 1877, p. 331), it consists, like an ordinary 

 walking limb, of seven joints, a. Basal joint fused to its fellow, 

 b and c. two median joints, d. Claw terminated by two to three 

 spines ; e. the sternum (?) displaced laterally. 



9. Poison claw. a. Appears to represent the enlarged basal joint fused 



to its fellow medianly; its anterior edge is produced into a process 

 bearing several stout spines, b. Joint prolonged internally into a 

 spine-bearing process, c. Two folds in the soft membrane connecting 

 b with d on the inner edge. They do not appear to represent 

 joints as they have been supposed to do. d. Large claw with the 

 opening of the poison duct at its apex. It is hinged at its outer 

 side upon b. 



10. First pair of limbs, with seven joints, a, b, c, d. The seven joints. 



It was supposed by Professor Rolleston that the double joints b, c, d 

 are formed by division of the joints similarly lettered in Fig. 8. The 

 terminal joint is generally regarded as a claw. It appears better 

 not to use for these joints the designations coxa, trochanter, femur, 

 tibia, and tarsus. They are all similar in aspect, not distinctly 

 differentiated in shape as are the parts so termed in Insecta. e. The 

 sternum. There is no tergum to this somite unless it is united 

 with the tergum of the preceding somite. 



The appendages, Figs. 8-10, are generally regarded as belonging to what is 

 called the ' basilar somite.' But the appendage, Fig. 8, is distinctly connected 

 with the head, and represents the labium of Insecta. In no Chilopod that I 

 have examined is a tergum present corresponding to the limb, Fig. 10, and in 

 some species this limb is absent. Balfour (Comp, Embryology, i. p. 325) is 

 inclined to doubt the correctness of Newport's statement to the effect that the 



