Stinkhorns are stomach fungi, with very different look and feel, compared to earthstars, earthballs or puffballs. These species propagate in two ways: by spore and by mycelium.

All in the Netherlands known species with a phalloid-shape start with an egg-shape. They are comencing as a (generally) white, silky egg-like structure full of yelly in which is embedded a conical cap attached only at its apex to a cylindrical white spongy, hollow stem (the so called receptacle). During growth the egg breaks open. From thre the stem is erecting with on top a slimy spore-mass.
The spore-mass on top is olive-green or brownish, and has a strong smell. Flies like the smell, are landing on it, and transporting the spores at their feet to different areas.

Mutinus species have little eggs (1-2 cm in diameter). In the Netherlands there are tree Mutinus species: de Dog's stinkhorn (Mutinus caninus), de Tapered stinkhorn(Mutinus elegans), and the Rosy stinkhorn (Mutinus ravenellii).

There is some resemblance with Common stinkhorn (Phallus impudicus).

Regional:

Two Mutinus species can be found in the Amsterdam area (het Gooi, Amsterdamse bos).

• Field attributes Dog's stinkhorn:

  Dog's stinkhorn has a orange-yellow to orange-red top an a weak smell of carrions. Dog's stinkhorn has relative thick and viscid gleba (as compared to Rosy stinkhorn), disappearing slowly, with a weak smell.
  

  Habitat Dog's stinkhorn:

  Dog's stinkhorn is rather common in the Netherlands, growing saprotrophe, in decidious woods, and parks at fertile humous and less-humous infertile dry sandy soils, and is observed in calciferous sandy soil (dunal coast) and non-calciferous sandy soil (pleistocene area).
  Dog's stinkhorn can be found from May till December (peak: Oktober).
  
  All the time I find Dog's stinkhorn's it is always either under beech (Fagus) or under larch (Larix), it is rare to find one under Pinus sylvestris, or other decidious trees, and I never have found one on shredded wood. All places were rather wet, in at that moment rather dry areas. I 've never found Dog's stinkhorn in dried areas which are in winter time wet or moisty areas.
   

• Field attributes Rosy stinkhorn:

  Rosy stinkhorn kenmerkt zich door een rozerode tot karmijnrode top en een vaak roze gekleurde steel. De geur ervan lijkt meer op kattepoep. Het schijnt qua herkomst een Noord-Amerikaanse soort te zijn.
  

  Habitat Rosy stinkhorn:

  
  Rosy stinkhorn is rather rare in the Netherlands, and grows on coarse litter and on humous soil, in parks, gardens, sphagnum-reedlands en hay-lands. Also on shredded wood and straw. Rosy stinkhorn can be found from June till November (peak: September till end Oktober).
   

Henk van Halm, in Rob Chrispijn e.a., Champignons in de Jordaan (1999), p. 164-165, reports both species in the Amsterdam Area. Rosy stinkhorn at shredded wood (on sand), and Dog's stinkhorn on mud (peat). Dog's stinkhorn is mostly found in the Amsterdam forest (beech).

During a guided tour in 2011 in Gaasperpark (Amsterdam), suddenly here was one, a Dog's stinkhorn, in the solely beech avenue there is over there.

I learned Dog's stinkhorn in 2000, from a mycologist who called this sixth finger Hondenlulletje (which means dog's cocky), a literal translation of 'caninus'.

Literature:
Rob Chrispijn e.a., Champignons in de Jordaan (De paddenstoelen van Amsterdam), Schuyt en Co, 1999, p.164-165.
Ewald Gerhardt, De grote Paddenstoelengids(voor onderweg), Tirion natuur, 2006,p. 618-621.
Roger Philips Paddestoelen van West-Europa, Spectrum, 2000, p. 257.
Hans Vermeulen, Paddestoelen, Schimmels en Slijmzwammen van Vlaanderen (determinatiesleutels aan de hand van kenmerken), De Wielewaal, Turnhout, 1999, p. 535