100 C/i. Brongniart — New Fossil Insect from the Coal- Measures. 



that these insects may maintain their equilibrium, the weight of the 

 abdomen must at least be equal to that of the head and thorax ; this 

 relative proportion is constant in the living species ; indeed, the 

 abdomen generally exceeds the wings in length by one or two 

 centimetres. 1 I am supported in this conclusion by a number of 

 examples. For instance, in a Phasmian which has a total length 

 of 16 centimetres, the head and thorax are 5| centimetres, and the 

 abdomen 11 centimetres long. We see that the abdomen is twice 

 as long as the head and thorax together. 



In the fossil, this part, the head and thorax, measures 4-| centi- 

 metres, the wings 8-J centimetres ; therefore, for the insect to be 

 in a state of equilibrium, the abdomen must have been about 10 

 centimetres in length. I make this statement with all reserve. 

 Another specimen of this insect, in a more perfect state, must be 

 discovered in order to justify this conclusion. 



The legs are perfectly preserved. The first two pairs are almost 

 of equal length, but shorter than the third pair. They are all 

 angular, and serrated, and in this respect they resemble those of 

 Cyphocrana, and differ from those of Phasmid^:. 



The trochanter is robust and short in the three pairs ; in the first 

 two pairs the femur is triangular, and is finely serrated along its 

 inferior margin. The tibia is also angular and serrated, and is 

 contracted near the proximal end ; it terminates in two points at the 

 distal end. The tarsi are alike in all the three pairs of feet, and are 

 divided into 5 joints, of which the first is the longest ; the last is 

 provided with a pair of recurved, pointed, and widely-divergent 

 claws, separated by a small rounded pad. The terminal articulation 

 of the tarsus is broadest at its distal end ; the three middle joints 

 are of equal length. The third pair of legs are the longest. The 

 femur is more robust and less angular than in the two other pairs, 

 and is armed with seven sharp spines along its lower margin. 



The tibia is angular, and bordered with fine denticulations, nine of 

 which are larger than the rest, and placed at regular intervals apart. 



The elytra of Protophasma do not offer any special characters, 

 and are of moderate size, measuring about one centimetre in length. 

 A stout longitudinal nerve marks the mesial line. 



The true wings, or the second pair, are quite distinct, but are 

 neither of them quite complete. Fortunately, what is wanting in one 

 is preserved in the other, so that I have been enabled to reconstruct 

 them, as seen in the accompanying plate (PI. IV. Fig. 2). In the 

 existing Phasmians, the wing is divided into two parts; the anterior 

 portion supported by three or four straight nerves, which reach to 

 the extremity of the wing, and united by irregular polygonal reticu- 

 lations ; the posterior portion traversed by slender and straight 

 nerves, which radiate, fanwise, from the base of the wing, and 

 which are united together by finely reticulating cross-nerves. 



The wings of Protophasma differ from those of the living 

 Phasmians. In the fossil form, the division between the anterior and 

 posterior portions of the wing is not so well marked as in the living 

 1 Except certain species -which have very short wings. 



