The egg of 0. moubata is among the largest known from ticks, 



A newly laid egg (Figure A4-) is slightly ovoid, glistening 

 golden yellow, and measures approximately 0.9 x 0,8 mm. Later it 

 becomes reddish brown. Eggs from older females are light to dark 

 brown in color. An irregxilar, faint, whitish, polygonal reticula- 

 tion and interrupted radiating strealcs may be seen throvigh the 

 cuticle. The internal larva becomes discernable four days after 

 the egg is deposited and occupies the whole egg by the sixth or 

 seventh day (Figures L5 and A6), ^An alkaline haeraatin product 

 originating from haemoglobin in the maternal blood meal has been 

 demonstrated in eggs (Wigglesworth 19^3), 7 



Eight days after the egg has been laid (temperature 30°C,), 

 the larva emerges by alternate contractions of the anterior and 

 posterior ends of the body (Figures 47 and A.8) that rupture the 

 shell (Figure 49) and expose the larval dorsal surface. The shell 

 may be completely detached in this manner, but usually remains on 

 the ventral surface covering the mouthparts and legs (Figures 50 

 to 54). /'Jobling_7 



When movements necessary for emergence are completed, the 

 larva becomes qujescent till the nymphal molt . That larvae are 

 nonmotile after hatching and do not feed has been conclusively 

 established for over a century, though severed recent textbooks 

 on medical entomology report differently. All observers have noted 

 the quiescent stage between hatching and molting, eind have differed 

 only in the time required for a larva to molt to a nymph, Davis 

 (1947) found that this molt occurred only a few hours after emer- 

 gence from the egg, Robinson (1942) and Jobling stated that lajrvae 

 molt four days after emerging from the egg (minimum, three days; 

 maximum, five days). The various early observers reported periods 

 of from three to 23 days from hatching till the nymphal molt, 



/"The sacculated gut of a newly hatched larva is filled with 

 a reddish brown fluid (Wigglesworth 1943). The inference is that 

 this is an alkaline haematin resulting from the ingestion of hae- 

 moglobin by the mother tick. "J 



Before molting, the larva pales in color; its legs ajid mouth- 

 parts shrink. Its skin becomes detached from that of the internal 



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