-222 
G. J. Snowball., 
The following table indicates a few variations in absolute time of stage 
<iuration for various conditions of rainfall and temperature : — • 
Table 2. 
Duration in days of each separate stage numbered. 
Date of 
Dropping. 
1. 
2 
3. 
4. 
5. 
Rain during 
period of 
disintegration. 
Temperature 
during period of 
disintegration. 
.20-3-41 
18 
1 3 
7 
* 
Nil 
20-6° C. 
J2-4-41 
2 
t 
8 
15 
* 
2-84" 
18*0'^ C. 
7-4-41 
1 
4- 
+ 
H 
10 
* 
1*50" 
17-6° C. 
31-5-41 
4 
8 
14 
* 
. . 
7-07" 
14-2° C. 
4-6-41 
8 
7 
29 
40 
* 
20-00" 
13-9'^ C. 
12-6-41 
9 
t23 
. . . 
41 
* 
17-14" 
13-9° C. 
22-6^1 
7 
18 
* 
. • • 
. « « 
5-52" 
14-2° C. 
23-7-41 
8 
3 
29 
* 
... 
6-86" 
13-9° C. 
-* Broken up in this stage. f -3 Duration of stage 2 plus 3 because they could 
not be separated. J Omitted. 
Insects are rarely responsible for tiie comj)lete destruction of a cow dung, 
this being accomplished by rain and other mechanical agencies. On the 
•other hand, c*akes may remain in the fifth stage for years without noticeable 
i^rosion. 
The cycle in a dung heap is substantially the same as that in a single 
cake, although the duration of the stages is usually greater because the inner 
portions are less accessible to disruptive influences. 
5. THE INSECTvS CONCERNED. 
The following is a list of the Insect Species associated with cow dung at 
Crawley, Western Australia : — 
CoUembola 
r : Hypogastruridae 
* Uuidentifled specimens 
Derniaptera 
F : n.,a!>iduridae 
Unidentified sjiecies 
Orthoptera 
F : Tettisoniidae 
Unidentified si)ecimens 
F : Gryllotaliddae 
Cj liiniracheta s\). 
ilemiptera 
F : Pentatomidae 
Unidentified sj)ecimens 
F : (’occidae 
Unidentified specimens 
Coleoptera 
F : Uarahidae 
Promecodcrus albanyensis, Cast. 
y : Hydropliilidae 
* Uei’cyon haemorrlioidalis. Fai). 
* Cercyon nicriceps, Marsh. 
V Parac'ymus sp. 
F ; Sta])hylinidae 
Ureophilus erythrocejfiialus, Fab. 
* Ury])tobiiim elegans, Blkb. 
* Le)itacinus socius, Fauv. 
Philonthus sp. 
Oxytclus spp. 
F ; Silphidae 
V Ciioieva sp. 
F : Tiichopterygidae 
V E))optia sp. 
? Philagai’ica sj). 
F : Histeridae 
Saprimis incisiis, Er. 
Saprimi.*< s])p. 
Hi.ster walkcri, Lea. 
Piatysoma ? nmltistriatum, Lea. 
1*' : Nitidulidae 
Uarpo])hiliis hemii)teriis, Linn. 
? Brachyjjeplus sp. 
F : Colydiidae 
Pabula dentata. Blkb. 
F : Ptinidae 
? Ptinus sp. 
* Breeding in cow dung. 
