62 E. G. WHELER ON THE NYMPH OF ORNITHOBORUS MEGNINI. 



I am unable to satisfy myself as to its probable use. The 

 presence of the tubercles, which from Neumann's description in 

 his " Revision de la Famille des Ixodides " appears to be peculiar to 

 the nymphal stage, may possibly be deemed sufficient to establish 

 a new genus for this species. He had not, however, noticed the 

 stigmatic organ contained within them. 



The species has other peculiarities. Neumann mentions the 

 unusual fact that the nymph attains dimensions at least as great 

 as the mature female, and that it is in this state that it acquires 

 the larger part of the reserves of blood which the latter utilises tO' 

 form its eggs. He also states that so great a difference exists. 



Fig. 1. 



Fig. 2. 



between the two states as to have caused Dr. Marx to believe- 

 them to be separate species. 



Descriptions of different stages of growth of this tick, with a 

 brief reference to the stigmatic organ, are to be found in the 

 ^'■Journal of the New York Entomological Society" for 1893, 

 pp. 49-52. It is well known in the States, and is mentioned as 

 having infested the ears of children. 



In general characteristics the species appears to be more nearly 

 allied to Argas than to Ornithodoriis ; but it seems probable that 

 it should be relegated to a separate genus, a contention that may 

 be strengthened by the fact that the first joints of all the legs are 

 almost entirely concealed beneath the cuticle of the body. But not 

 having had an opportunity of examining an adult specimen, I 

 should be sorry to express any definite opinion on the subject. 



Joiirn. (^iukett Microscopical Club, Sir. ~, Vol. VIII., No. 48, April 1901. 



