rnvLLoron cuASTArEV of .tapax. ■ 19 



The species was first discovered by myself in small pools formed by 

 rain water collected in depressions on tae sandy sea-sbores at Kngenuma in 

 the province of Sagami. during tbe months of .Tnly and August, 189'2. These 

 pools were f(^rmed after a heavy rain at the end of Tnly that year, and the 

 lirst trace of the animals were observed a week afterwards. These were 

 already quite mature, the females carrying numerous eggs laid under the 

 shell. Associated with this species many aquatic beetles, bugs, mosquito- 

 larvtp, and a species of Branchipus hereafter to l)e described, were plentifulls' 

 found in the jiools, the water of which always remained perfectly clear 

 its temperature rising in hot days to 88° or even 89^ C. The continued 

 dry weather of August dried them U]) at the end of the month, so that 

 the pools existed only for about a month, dinving which time only one gamo- 

 genetic generation was found. 



EUIiOrNADIA TACKAEDTANA, n. spec. (PL VIT, 1-n). 



Female (Fig. 1) : — -Shell-valves nearly of the same shape as that of the 

 preceding species, but is of tougher consistency, with six lines of growth, 

 two of these lines lying close to the border of the shell, ai'e only seen by 

 moderate magnification. The shape and the structure of the shell-gland, and 

 the maxtrix of the shell are also quite similar to that species. The position 

 of the adductor muscle of the shell is, however, more anterior, approaching 

 in this respect more to that of Ti. Stanleyana. In the lateral view of the 

 head, the lower angle more rounded ; tbe posterior border of the median eye 

 nearly straight. The tip of the lip more produced, and the hepatic lobes 

 larger and fewer in number. ' -. ■< 



The first antemia^ short, nearly half as long as the Imsal portion of the 

 second, provided with five or six sensory lol)es. IHie second antenna' with 

 about eight jointed basal portion, and with eight or nine jointed upper and 

 nine jointed lower tlagellum, the setn^ on all the joints similar to those of the 

 preceding species. 



Eighteen pairs of legs. The first leg (Fig. 2) is also similar to that of 

 the Kugenuraa species ; its first endite with rmly one serrated hook-like spine 

 and with about twenty-four feathered seta:- ; the second eiidite with seven- 



