62 JOURNAL, BOMBA Y NA TURA L HISTORY SOCIETY, Vol. XIV. 



with strong lateral spines on the first segments. (^Forcipula), and sometimes 

 the aides of the segments are laterally produced into strong recurved hooks 

 {Ancistrogaster^ The form of the anal segment, which varies considerably 

 with the species, is an important character. There is no exserted ovipositor. 

 The subanal plates bear a small projection between the legs of the forceps 

 called the pygidium which is a useful specific character. 



The FORCEPS are homologous with the cerci of other Orthoptera. They 

 are horny and unsegmented, of varying shape, which differs even in indivi- 

 duals of the same species ; they are always more simple in form in the $ 

 than in the ^. In the genus Diplatys, Green has shown that these organs 

 are long and segmented in the larval stages. In the penultimate stage 

 they are lost, except the basal segment, which becomes transformed 

 into the well-known forceps. The process very probably takes place in 

 other genera, but in very young Pygidicrana-la.vv3d there is no visible 

 trace of segmentation in the already formed, though simple, forceps. 

 The forceps of the larvae usually resemble those of the adult ^. Their 

 function is uncertain. 



The LEGS are formed for running, and offer few characters. The second 

 tarsal segment is very small, and may be simple and cylindrical, as in many 

 genera, or produced into a long lobe beneath the third segment, as in Cheli- 

 oc^es, or simply lobed or heart-shaped, as iv Fo7'Jicula,ete,, etc. In some 

 cases, however, the first segment is no longer than the second (^Apachys), but 

 this is said not to be very constant. 



There is a pulvillus between the tarsal claws, but this contracts and 

 shrivels on drying, and so is useless as a character. 



The EGGS are simple leathery bags, and are all laid teparately, i.e., not in 

 an ootheca, as in Blattodea, etc. It is a remarkable fact that the mother 

 earwig shows a certain degree of interest in her eggs, and even in the young 

 larvae after they are hatched. The eggs are usually deposited under a large 

 stone for protection. 



The LARV.^ are always more lightly coloured, the integument is -softer, 

 the forceps more bimple, than in the imago, but it is often difficult to distin- 

 guish them from the adult in the apterous forms. The larvae, however, 

 shrivel up on drying, while the harder and horny imagines retain their shape. 

 In the winged forms the sculpture of the wings is visible upon the notal 

 plates at an early stage. 



The phenomenon of GYNANDROMORPHISM® is: not unfrequent in 

 earwigs and has been recorded in several species. The asymmetry of the for- 

 ceps is at once noticeable. 



*More frequently it is probable that the so-called cases of (jiynandromorphisra are merely 

 malf s with one branch of the forceps undeveloped, i.e., sinjple and resembling those of the 

 female. In all the instances that I have seen, there have been nine abdominal segments visiblej 

 as in the normal male. 



