Deutonympha (Fig. 1 and 2). Length: 440 p. Colour: white. — 

 Shape like that of the protonympba, imtnediately, howev'er, distin- 

 guishable from it by its larger posterior dorsal shield and by its 

 longer bristles. The specific characters : four intermediate shields and 

 four bristles on the posterior dorsal shield are present. The ventral 

 side shows us an anal shield which is truncated anteriorly. The 

 peritrema is not longer than that of the protonyrnpha. 



Female. The feinale seems to be oviparous, for one of my female 

 bears au egg with a distmet shell. The surface of it shows a reticul- 

 ation with almost hexagonal meshes. I thiiik such a shell would 

 not be formed if the animal were viviparous, like e. g. L. lobatus Klti. 



2. Liponyssus lobatus Kit. 



With Plate I fig. 3—17. 



Larva (Embryo). I have dissected this larva from the uterus of 

 a female. Fig. 3 shows us an embryo (larva) within the envelops. 

 Distinctly visible are : the two mandïbles, the two maxillae, the two 

 maxillar palps, three pairs of legs, the lst and 2d femur already 

 provided with the two bristles so characteristic in the whole 

 subfamily of Dermanyssinae, and two pairs of hairs behind the 

 anus. It measures 360 fx. 



Larva (Embryo). I have treated during 5 miuutes this embryo 

 with a solution of caustic kali of about l5°/ in a temperature 

 of 50° C. It stretched its legs, the envelops burst and the larva 

 got free (Fig. 4). The legs are provided with all the hairs of the 

 nymphae and adults! On the femur 1 and 2 the two characteristic 

 bristles are discernable. On the dorsum 9 pairs of minute hairs 

 are present alrnost corresponding with those of the anterior shield 

 of the nympha. More backward one pair of minute hairs, and 

 quite posteriorly 6 pairs of singular curved, distally knobby hairs, 

 not corresponding with any hairs of the nympha or adults. 



Remark. Berlese's assertion that the Dermanyssinae are oviparous 

 (Mesostigmata p. 18) seems to be premature. Here we have a 

 viviparous one, bringing forth larvae, whilst Spinturnicinae bring 

 forth nymphae! 



