146 Remarks on some Parasites 



be satisfactorily claimed as such. The head is very much depressed 

 — if head it can be called — is somewhat of a pentagonal figure, the 

 two stout chelicerae forming four of the sides (the apex projects as 

 a double point), the base or remaining side being made by the attach- 

 ment to the body (vide Figs. 1, 2). The "instrumenta cibaria" 

 (Fig. 7) are placed within a sort of neck, like the top of a tied 

 sack ; the labrum appears to consist of a thin chitinous plate united 

 posteriorly to the cervico-thoracic ring, and in the middle on the 

 under surface, to two long stylous processes, al, connected with 

 the maxillae a, situated either side of the median hne, and laterally 

 to the basal joint of the chelicerae. It overlies a complicated 

 framework that forms or supports the maxillae, and that branches 

 backwards by two curved processes, to be apparently hinged 

 to two incurved processes arising from the thoracic attachment. 

 The middle portion of this framework looks to be enfolded inter- 

 nally, and to be connected to two stout inwardly-curved parts, a, 

 strongly tipped with chitine at the ends, and supporting on the 

 anterior and outer portions a feathery bristle — which pieces taken 

 together may probably be said to form the labrum, superior maxillae, 

 and maxillary palpi, al, a,h. Beneath are two portions, e, form- 

 ing the basal joints that support each a stout curved tooth, slightly 

 indented (Figs. 10, 11). In the natural position they are placed 

 side to side ; but when in action cut or tear horizontally, and repre- 

 sent the inferior maxiUae: applied together and with the inner 

 portions of the upper maxillae, they form a more or less perfect suc- 

 torial tubular cavity; situated laterally and strongly attached to 

 the cephalic framework at their bases are two stout conical che- 

 licerae, four jointed, and supporting a long'bifid tooth or claw, e, 

 having at its base on the inner side a compound feathery brush, d. 

 The inferior lip seems to consist of a thinnish chitinous membrane 

 that unites these parts inferiorily and laterally, to which is attached 

 what appears to be a saccular eversion of the ligua or pharynx under 

 compression, as in the example from which the figure was taken, 

 almost the whole of the granular contents of the abdominal cavity 

 were ejected through the mouth from the pressure. This hgua (?) 

 has two conical processes (? glandular) and a circular opening, /. 

 At the cervico-thoracic junction on the upper surface, behind, is a 

 thin chitinous plate with a waved or curved outline, sujoporting three 

 fine hairs on the front and four near the back edge, the two lower 

 central ones being much larger than the others, (?) ocellar at the 

 base ; though more laterally on the same line are seen two some- 

 what opaquish oval projections, which may be visual organs, and 

 beyond these on the same sweep of curvature, two equal if not a 

 trifle larger areas than the central ones are visible, which are sus- 

 pected to be tracheal orifices. The laxity of the tissues after the 

 use of hquor potassae, and the great displacement that occurs in 



