THE ENTEROPNEUSTA. 
TABLE 1. 
Ptychodera flava, var. parva. 


645 








8 
v 






No. of specimen (1) (2) (3) (4) (5) 
IPLODOSCIS|COCLOM:......-c.ccoscss eens Spacious. Ca- as (1) as (1) as (1) as (1) 
vity with dis- 
tinct outline 
Collamicoclomirccscccsesssesseseees Very spacious as (1) as (1) as (1) as (1) 
Ventral proboscis septum ......... To tip of sto- as (1) as (1) as (1) Almost to tip 
mochord of stomochord 
Dorso-ventral proboscis muscles Present as (1) as (1) as (1) as (1) 
Dorsal collar septum ............... Complete after as (1) as (1) Complete just as (1) 
1st root before 1st root 
Ventral collar septum ............ Absent as (1) Complete — at as (3) as (1) 
hind end of 
collar 
IRACEMOSE OFFA) .c.ecsccesssessescces Small and un-| Well marked as (2) as (2) as (2) 
lobulated but unlobu- 
lated 
Dorsal proboscis muscle decussa- | Small. No ven- as (1) as (1) as (1) as (1) 
tion tral circular 
ruse. fibres 
WorsaliOotsenc.-s-cectereseecaseer *Rrr RRr RR Rr RR 
IETOUOSCISIPOLESI c= sdecesertaedcessee *LR LR LR LR LR (opening 
together) 
IN@GVe;COrdy sessaeaccceeeressdesoesess Lumen com-| Lumen with} Lumen with as (1) as (1) 
plete through- | fainttendency | very faint 
out to occlusion tendency to 
occlusion 
Length of post-branchial groove e 
= “16 — . ‘16 
Length of branchial region 2 i Ie 
fpbceed Moonen a ee 21-2 26°5 22'8 21-7 21-0 
| Length of collar 
| 
| y | He je 5 
Circumference of branchial ces. Vi 1-05 1-06 1-04 1-07 
Circumference of cesoph. ces. 
| PSHVME SALLI Goccessoodooabcoscenoqdan6 Not more than | Not more than as (1) as (1) as (1) 

* R denotes a dorsal root reaching to the epidermis, r an incomplete root which does not extend to 
the epidermis. 
and places the proboscis coelom in communication with the exterior a capital letter is used. 
pore is not thus functional it is denoted by a small letter. 
Of the proboscis pores L represents the left and R the right one. When the pore is functional 
When the 
Trunk. The branchial region, as has already been seen, is in this variety relatively 
short. 
of the branchial region. 
G. IL. 
The post-branchial groove is moderately well developed and is about } 
The genital folds in the region of the branchiae are large 
of the length 
83 
