Details of parts of Milkweed flower

PLEASE H E L P PLEASE : 8 posts by 4 authors. Attachments (1)
To make this plate I copied two photographs recorded by … Please help me to understand different floral structure of an asclepiad flower. Please check all label and let me know which are wrongly marked.

Please find the attached image which may answer your query! Link for the image is here: 

Thank you very much …, it is very similar to 
It appears to me that what is “corpusculum” in this plate is same as “gland” in the above page.
It appears to me that my/… plate is ok.

I don’t know which question mark stands for which question, but you need to spend some time to find a plant in flower and open up the flower and you will know where pollinia is.

What you pointed at pollinia is not pollinia, IT IS A SAC INSIDE WHICH ONE LOBE OF POLLINIA IS HIDDEN (PUT YOUR PENCIL TIP ON THE GLAND AND PULL IT OUT TO SEE POLLINIA) and what you pointed as ‘what is this?’ is called GYNOSTEGIUM (KIND OF A STAGE ON WHICH MALE AND FEMALE PARTS ARE LOCATED IN THIS SECTION OF APOCYNACEAE). Outer corona is the CORONA HOOD, inner corona is the CORONA HORN. 

What a insight inside, …!
Pollinia = “paired sacs of pollen“
&
“What you pointed at pollinia is not pollinia, IT IS A SAC INSIDE WHICH ONE LOBE OF POLLINIA IS HIDDEN“
The pair of statements above tells me what I pointed at = A SAC INSIDE WHICH ONE LOBE OF PAIRED SACS OF POLLEN IS HIDDEN

Gynostegium = “anther + stigmatic disc“.
&
“what you pointed as ‘what is this?’ is called GYNOSTEGIUM“
The pair of statements above tells me = NUMBER OF GYNOSTEGIUM IN THE PLATE I HAVE LABELLED IS FIVE, OF WHICH TWO ARE MARKED BY BLUE ARROWS

Corona = “hood + horn“
&
“Outer corona is the CORONA HOOD, inner corona is the CORONA HORN“
The pair of statements above tells me = THOSE ASCLEPIADS WHICH HAVE SINGLE CORONA WILL EITHER HAVE HOOD OR HAVE HORN

So kind of you, …

Pollinia = “paired sacs of pollen“

&
“What you pointed at pollinia is not pollinia, IT IS A SAC INSIDE WHICH ONE LOBE OF POLLINIA IS HIDDEN“

The pair of statements above tells me what I pointed at = A SAC INSIDE WHICH ONE LOBE OF PAIRED SACS OF POLLEN IS HIDDEN
Pollinia IS NOT EQUAL TO PAIRED SAC OF POLLEN. Pollinia is a structure which is formed of two lobes of pollen mass adhered together with a Y shaped caudicle also called as TRANSLATOR ARMS and gland at the end of Y which is sticky, also called as VISCIDIUM in some cases, to get on the insect legs or other body parts. Pollen sac is usually referred to a sac like structure inside which these lobes hide FREELY. Basically you cannot see the pollinia unless you take it out. Once you take it our, the pollen sac stays back on gynostegium as it is an integral part of the gynostegium.
Gynostegium = “anther + stigmatic disc“.
&

“what you pointed as ‘what is this?’ is called GYNOSTEGIUM“

The pair of statements above tells me = NUMBER OF GYNOSTEGIUM IN THE PLATE I HAVE LABELLED IS FIVE, OF WHICH TWO ARE MARKED BY BLUE ARROWS
GYNOSTEGIUM IS NOT ANTHER + STIGMATIC DISC.
DID I TELL YOU THERE ARE 5 GYNOSTEGIUMS? Gynostegium is the complete structure which is formed by the fusion of androecium and gynoecium. Once fused this is a single structure that is SINGLE GYNOSTEGIUM which can have five lobes BUT NOT 5 GYNOSTEGIUM.
Corona = “hood + horn“
&

“Outer corona is the CORONA HOOD, inner corona is the CORONA HORN“

The pair of statements above tells me = THOSE ASCLEPIADS WHICH HAVESINGLE CORONA WILL EITHER HAVE HOOD OR HAVE HORN
CORONA IS NOT HOOD + HORN
OUTER CORONA AS PER YOUR LABEL AND INNER CORONA AS PER YOUR LABEL. I never said there are two corona. Corona is infact part of petals modified to form some structure which can be simple papillae as in Viola or long appendages as in Passiflora. In your pic corona is single circle of structure, and it can be divided into corona hood and corona horn ALSO REFERRED TO AS CORONAL HOOD AND CORONAL HORN.

So please read my comments properly before giving your interpretation.

Orchids and Asclepiadaceae are very similar in some aspects thats why I wanted to explain. The most interesting part is how and such different plant family are so similar!! No one knows…..

Keep up with your curiosity and many interesting discoveries in the world were made just because some people were more curious than others.

Hoya (Asclepiadaceae-now under Apocynaceae as distinct subfamily) and Orchidaceae are surely an example of convergent evolution.