172 Blackburn and Harrison . — The Status of the British 
Once more we discovered that we were dealing with members of the 
pentaploid group with a somatic chromosome complement of thirty-five, as 
Text-fig. 3, b , from R. 'Reuteri will suffice to show. 
Except for one single point, that we fancied the synaptic knot to be 
tighter than in the allied R. coriifolia, the cytology of the two Afzeliana 
types, completely coincides. Text-fig. 3, g, from R. stephanocarpa will 
prove that this is the case as far as the arrangement of the chromosomes 
is concerned. There the seven bivalents can be made*out surrounded by 
Mg, 
~R coTil-foli 
'ICf**- 
‘R.'ReuteT-i 
f 4 & ~ m 
.«>. 
i 
Si 
"Kcoriitontx 
/%•«> 
C 
'A 
-nvd 
^ o Kf 
*a> 
"R.Luhetiana 
"f?.Tub'g'i.no&a 
'R.s>v've&tri& 
* 
• •> 
• 
Is % 
T? U 1- bica 
pb.a^oca.Ypa 
k 
j § 
d>: 
"R. rub'igiuo&a 
1 veatri 
■R. pa/ns'ie-ns'ia 
Text-fig. 3. The pentaploid roses. Somatic and heterotype equatorial plates. 
x 3,000. 
the complementary univalents. Giving due weight to their agreement, no 
additional treatment seems necessary. ‘ 
. 1 
(b) The Eucaninae . 
To us the term 5 Eucaninae ’ covers all the ‘ ultra ’-microspecies ranged 
in Wolley-Dod’s list under the canina and dumetorum groups ; it thus 
appears as an aggregate systematically, if not genetically, equivalent to 
a collective species. 
We regard R. dumetorum , once deemed a very important macrospecies, 
as quite an unimportant entity when placed alongside its associates. 
Notwithstanding this, to indicate precisely what forms we have 
studied, we give their names as set down in the list to which we have 
