178 Malformations in Ticks 
the coxal armature of both is reduced to a single, stout, conical spur, which 
projects almost perpendicularly from the ventral surface. The corresponding 
coxae of the opposite side are normal, and are figured for the purpose of 
comparison. 
Specimen 4. 
Hyalomma aegyptium (L.), $ (N. 3347), off Hemitragus hilocrius, Cochin 
State, Madras, India; received from the Indian Museum, Calcutta. The 
specimen presents a considerable degree of asymmetry, due to an oblique 
curvature of the axis of the body. This is the most frequently occurring type 
of malformation in ticks. The fact that the scutum is also malformed, would 
appear to exclude the possibility that the distortion has been caused by 
unequal distension during the act of engorgement, a cause to which the 
condition often may be attributed. 
Fig. 5. Hyalomma aegyptium Abnormal: suppression of spiracle and adanal 
shields on right side of body. (L.E.R.) 
Specimen 5. 
Hyalomma aegyptium (L.), (N. 26 c), off goat, Germiston, Transvaal, 
S. Africa, 6. iv. 1918. The specimen was sent by Dr B. G. Brock. The posterior 
portion of the body is asymmetrical; the right spiracle is completely absent, 
and the adanal shields are reduced to vestiges on the right side. On the left 
side of the body, all of these structures are normal. 
Such malformations as those described above, are probably the result of 
some mutilation of the tick during the course of the preceding nymphal 
phase. Experimental investigations of the power of regeneration of injured 
or amputated appendages, as manifested by ticks, have shown that this 
